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Investigating the Diversity of Life

Grade Six Life Science FOSS Unit and Immersion Investigations

Unit Overview

Field Testing This unit is being developed through collaborative work among the Madison Metropolitan School District (MMSD), the University of Wisconsin-Madison, and other contributors participating in the SCALE Math and Science Partnership (System-wide Change for All Learners and Educators), funded by the National Science Foundation. Preliminary field tests were conducted in two sixth grade classrooms in MMSD. Additional field testing and subsequent drafts are part of the ongoing unit development that will continue through the 2006/2007 school year. Please share your insights and suggestions by contacting Hedi Baxter at UW–Madison ([email protected]) or Sue Johnson at MMSD ([email protected]).

Unit Overarching Concepts

• All living organisms—single and multi-cellular—have to solve the same set of problems to survive and do it in a variety of ways through physiological, behavioral and structural adaptations.

• Scientific progress is made through inquiry.

Unit Supporting Concepts 1. Some things are living (alive, dead, dormant) and some things are non-living

(never living). 2. Environments are made of living and nonliving things. 3. Some living organisms are microscopic. 4. Living organisms are made of cells (and cells contain organelles). 5. Plants are living and have specialized structures 6. Animals are living and have specialized structures and behaviors. 7. Scientific investigations involve collecting, analyzing and applying relevant

evidence to support explanations. 8. Scientists use evidence from investigations and other sources to help explain

their questions about natural phenomena. 9. Scientists communicate and justify their explanations to other scientists using

evidence, and revise explanations based on new evidence.

Evidence of Student Understanding Evidence that students understand that all living organisms—single and multi-cellular—have to solve the same set of problems and do it in a variety of ways through physiological, behavioral and structural adaptations:

• Students formulate explanations for how key cellular structures have particular functions that make it possible for the cells that contain them to meet their needs and, in multicellular organisms, work to help the whole organism meet its needs for life.

• Students explain the role of specialized cells in a multicellular organism and how they affect an organism’s ability to meet the “needs.”

o Explain how organisms interact with their environment by investigating crayfish and cockroach preferences

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mailto:[email protected]

INVESTIGATING THE DIVERSITY OF LIFE UNIT OVERVIEW • Students compare and contrast some advantages/adaptations between types of

organisms studied in the unit o Discuss and chart as each is studied, then do a culminating comparison

• Students identify the way scientists meet stem cells’ basic needs and compare/contrast to nature.

• Students explain that stem cells are the common ancestor of a human’s cells and that they differentiate, producing specialized cell types.

Evidence that students understand that scientific investigations involve collecting, analyzing and applying relevant evidence to support explanations: • Students develop and pose questions about a disease/condition and how it impacts the

afflicted organism’s ability to meet its needs. • Students explore a variety of resources about how scientists understand disease and use

that knowledge to construct a scientifically-oriented explanation for how the afflicted organisms’ ability to meet its basic needs is impaired.

• Students communicate to their teacher and classmates their explanations for how their chosen disease/condition interferes with an afflicted organisms’ ability to solve the “problem(s)” faced by living organisms, what levels (located in the “ribbon of life”) are affected, and justify their reasoning with evidence.

Unit Preview Throughout their studies in the Diversity of Life, students build on their understanding from the previous life science units that all living organisms have basic needs that must be met to live. From the 7 basic needs identified and charted for all organisms and cells studied during the FOSS Diversity of Life Unit, students ask questions to learn about the eighth characteristic that living organisms share that is explored in this unit, that all organisms are made of cells. By asking questions, researching for evidence, and constructing explanations about how organisms are able to meet their needs at the cellular and multicellular levels, students have an opportunity to appreciate both the similarities and differences in how diverse organisms meet the needs required for life. The FOSS Diversity of Life investigations are designed to show students to a wide variety of organisms, from single– to multi–cellular animals, plants, bacteria, fungi and protists with an underlying theme of exploring how each meets its needs. In addition to the FOSS materials, an ongoing graphic organizer used to track the accumulating learning about different kinds of organisms and three Immersion Investigations are built into this Diversity of Life Unit for MMSD. A development team that included classroom teachers, scientists, district science leadership, and curriculum developers worked together to identify ways to refine the FOSS materials to support students in learning for understanding the key concepts identified by the Wisconsin Science Model Academic Standards and Framework. After completing FOSS Investigation 4, students are given an opportunity in Immersion Investigation 4A to investigate the structure, function, and primary locations where basic organelles and cellular structures can be found. By asking questions about how organelles like mitochondria and nuclei and structures like the cell membrane help particular cells meet their basic needs, it becomes clear that not all cells are the same. Then students are guided to look for patterns in which types of cells contain certain types of structures. Developing and sharing explanations for those patterns provides a way for students to demonstrate their understanding that specialized cells are different in structure and function, and that specialized cells working together make it possible for multicellular organisms to meet their needs.

Investigating Diversity of Life DRAFT 2

INVESTIGATING THE DIVERSITY OF LIFE UNIT OVERVIEW In Immersion Investigation 4B, students further explore diversity in structure and function. This investigation involves students in an inquiry about a variety of different cell types that are found in humans and other animals, Students have an opportunity to demonstrate their understanding that multi–cellular organisms are made of diverse and specialized cells, and the individual cells in a multicellular body may not be capable of staying alive individually. In this investigation, students research and compare two very different cell types and observe slides of the cells, using a microscope. After reporting their findings, the class is introduced to stem cells and guided to realize that these cells that are very different from any of the cells researched are actually the originating cells for all the diverse cells studied. Recognizing this important connection among all the diverse cells that the class explored introduces students to the important idea of common ancestry. Immersion Investigation 4C is a lesson intended as a benchmark assessment to gauge student understanding of how cells meet their basic survival needs, using the example of real scientists maintaining cells in the research laboratory. The unit proceeds with students continuing to explore how plants meet their basic needs. Then, the idea that organisms have special adaptations that are particularly well–suited to their environment is introduced. Students observe and investigate crayfish (in place of the snails recommended by the FOSS kit, as those are not readily available) to learn about their structures. In Immersion Investigation 9A Observing Crayfish and Cockroaches, students explore adaptations more deeply by investigating animals that are similar (both are arthropods) and yet very different (living in an aquatic versus terrestrial environment). The final FOSS investigation provides a brief introduction to how scientists use kingdoms to classify organisms. In addition, there is an optional activity in which students explore foods that are examples of how humans depend on all types of organisms, including microorganisms, in daily life.

Investigating Diversity of Life DRAFT 3

GATING THE DIVERSITY OF LIFE UNIT OVERVIEW

of Life DRAFT 4

INVESTI

Diversity

Unit Standards

Concept Alignment: Grade 8 Framework

1- key concept 2-concept introduced or included as a supporting concept 3- concept indirectly referenced

Wisconsin Model Academic Standard Grade 8 Framework

Grade 6: Diversity of Life and Immersion

Investigations

Understand the organisms are composed of cells and that cells are the basic unit of life. 1

Explore cell components, including different components of plant and animal cells. 1

F.8.1 Understand the structure of cells, organs, tissues, organ systems and whole organisms

Apply cell specialization to the organization of tissues, organs, systems and organisms in both plants and animals (photosynthesis and respiration on a conceptual level). 2

Compare form and function of various organisms’ adaptations as related to their environments.

2

F.8.2 Show how organisms have adapted structures to match their functions, providing means of encouraging individual and group survival within specific environments.

Investigate natural selection. x

F.8.3 Differentiate between single-celled and multiple-celled organisms (including humans) through investigation, comparing the cell functions of specialized cells for each type of organism

Investigate a variety of cells, including single-celled and multiple-celled organisms, plant and animal cells using microscopes and illustrations. 1

INVESTIGATING THE DIVERSITY OF LIFE UNIT OVERVIEW





Investigations

Emphasis should be on conceptual understanding of differences between single-celled and multiple-celled organisms.

2

Compare and contrast structure and function of specialized cells such as: muscle, nerve, blood in animals or transport, photosynthetic cells in plants. 1

Investigate basic genetics including Mendel’s theories, Punnett squares and predictions of possible offspring. x

F.8.4 Investigate and explain that heredity is comprised of the characteristic traits found in genes within the cells of an organism

Understand that genes determine traits. x

F.8.5 Show how different structures both reproduce and pass on characteristics of their group

Study sexual and asexual reproduction with emphasis on the advantages and disadvantages of each.

x

F.8.6 Understand that an organism is regulated both internally and externally

Investigate external/internal stimuli on organisms using themes of equilibrium and constancy. Examples: stimulus/response, feedback loop, diffusion/osmosis within cells, body temperature regulation.

x

Diversity of Life DRAFT 5






Investigations

F.8.7 Understand that an organism’s behavior evolves through adaptation to its environment

Study organisms behavioral modifications to their environment. Examples: hibernation, fluffing feathers, migration, nesting, shivering, huddling, herding, caring for young x

Investigate interactions within various ecosystems and their components (including non-living).

x

F.8.8 Show through investigations how organisms both depend on and contribute to the balance or imbalance of populations and/or ecosystems, which in turn contribute to the total system of life on the planet

Analyze population fluctuations and energy flow in ecosystems.

x

F.8.9 Explain how some of the changes on the earth are contributing to changes in the balance of life and affecting the survival or population growth of certain species

Investigate environmental problems. Examples: invasive species, extinction, overpopulation, degradation of habitat, exceeding carrying capacity, drought, etc.

x







Investigations

F.8.10 Project how current trends in human resource use and population growth will influence the natural environment, and show how current policies affect those trends

Study current policies and their impact on our environment.

x



Grade 8 Performance Standards: Key Concepts Included in The Diversity of Life Unit and Immersion Investigations

A.8.3 Defend explanations and models by collecting and organizing evidence that supports them and critique explanations and models by collecting and organizing evidence that conflicts with them

A.8.4 Collect evidence to show that models developed as explanations for events were (and are) based on the evidence available to scientists at the time

B.8.3 Explain how the general rules of science apply to the development and use of evidence in science investigations, model-making, and applications

B.8.4 Describe types of reasoning and evidence used outside of science to draw conclusions about the natural world

C.8.1 Identify* questions they can investigate* using resources and equipment they have available

C.8.2 Identify* data and locate sources of information including their own records to answer the questions being investigated

C.8.3 Design and safely conduct investigations* that provide reliable quantitative or qualitative data, as appropriate, to answer their questions

C.8.4 Use inferences* to help decide possible results of their investigations, use observations to check their inferences

C.8.5 Use accepted scientific knowledge, models*, and theories* to explain* their results and to raise further questions about their investigations*

C.8.6 State what they have learned from investigations*, relating their inferences* to scientific knowledge and to data they have collected

C.8.7 Explain* their data and conclusions in ways that allow an audience to understand the questions they selected for investigation* and the answers they have developed

C.8.8 Use computer software and other technologies to organize, process, and present their data

C.8.9 Evaluate*, explain*, and defend the validity of questions, hypotheses, and conclusions to their investigations*

C.8.10 Discuss the importance of their results and implications of their work with peers, teachers, and other adults

C.8.11 Raise further questions which still need to be answered

G.8.2 Explain* how current scientific and technological discoveries have an influence on the work people do and how some of these discoveries also lead to new careers



Assessing Student Understanding The focus for this unit will be on continuous assessment—the day-to-day observation/documentation of student work for the purpose of moving them forward in their understanding and practice of science. Continuous assessment is an inquiry into what students know and are able to do. The following section contains ideas for teachers to assess and document student learning throughout the unit for the purpose of modifying instruction and ensuring student learning using a variety of assessment techniques.

SUMMATIVE ASSESSMENT Summative assessment refers to the cumulative assessments that capture what a student has learned and is able to do. They also can assess student performance based on standards. Summative assessments are often thought of as traditional objective tests but this need not be the case. For example, summative assessments can be an accumulation of evidence collected over time, as in a collection of student work or a science notebook. Summative assessments are often performance-based, requiring students to actively engage in activities such as writing, presenting, demonstrating, manipulating materials, and applying their learning in multiple ways. Within this unit, there are several opportunities for formal documentation of student progress. These techniques provide the teacher with information about student learning for instructional decision-making as well as a tool for formal reporting of student progress.

FORMATIVE ASSESSMENT Formative assessments provide information to students and teachers that is used to improve teaching and learning. These are often informal and ongoing. Many opportunities for formative assessment are embedded in this unit. Students will be asked to respond both in writing and orally to a variety of prompts and use charts and data tables. Student Pages are provided to both support and guide student learning and make their thinking evident to the teacher. These pages can be used as a portfolio to represent the work of each student. The student pages can be periodically collected and reviewed to help the teacher assess the progress of each student. In addition to the student pages included in this unit and in the FOSS binder, students will maintain a science notebook. They can record observations, take notes on readings, record questions that come to mind, and write responses to questions. The science notebook can be used as both a self-assessment tool as well as a record of student learning for documentation purposes.

FORMATIVE ASSESSMENT TOOL: REAPS REAPS is a method of formative assessment that combines the time-tested ideas of Bloom’s Taxonomy with new research on student assessment. The level of thinking increases from basic recall to complex analysis and prediction. On each Lesson Snapshot page is a series of REAPS prompts. This series of prompts is a simple tool that can be used throughout or at the end of each lesson. They can be used with students individually, in pairs, or in groups to review what they know and are able to do. This provides an opportunity for the teacher to modify instruction as necessary based on student responses. The prompts increase in cognitive difficulty with Recall as the easiest and Predict as usually the most advanced. Students will most likely demonstrate confidence and ability when responding to the first few prompts, while demonstrating continuous improvement in responding to the Apply and Predict prompts. Students are not expected to master all of the skills, but are encouraged to extend their thinking. Suggested responses are included in italics after the prompts. While these are good responses, other responses may be valid with supportive evidence and reasoning.

The following is a description of the types of prompts included in the REAPS. R Recall knowledge: Determines whether the student has learned the basic knowledge that is related to

and supports the key concept including lists, drawings, diagrams, definitions. E Extend knowledge: Determines whether the student can organize the basic knowledge related to the

key concept such as compare, contrast, classify.



A Analyze knowledge: Encourages the student to apply or interpret what they have learned including developing questions, designing investigations, interpreting data.

P Predict something related to new knowledge: Engages the student in thinking about probable outcomes based on observations and to engage them in a new topic that builds on prior knowledge.

S Self/Peer Assess: Encourages students to take responsibility for their own learning. Includes methods and/or activities for students to assess their own learning and/or that of their peers.

FORMATIVE ASSESSMENT TOOL: SCIENCE NOTEBOOKS Many research studies establish the benefits of using science notebooks as a place for students to record data, questions, drawings, explanations, and other ideas. Immersion Unit field test teachers report that students benefited from having a science notebook that includes students’ thoughts and questions as well as the Student Pages that are completed throughout the unit. Students refer to data from previous tests/observations, look up the names of animal structures on previous Student Pages, compare drawings to current conditions, and learn about this important tool that working scientists use––their science notebook. The notebooks also serve as a tool for assessing student growth and communicating student achievement to parents.



Unit Graphic Organizer To help students make connections among the concepts they learn as they investigate a wide variety of organisms, it is recommended to use a graphic organizer to track key ideas from each investigation in the FOSS unit as well as the Immersion Investigations. The categories in the graphic organizer revolve around how any organism studied meets its basic needs, the seven unifying characteristics of living things that are referenced throughout the FOSS unit.

DIVERSITY OF LIFE: BASIC NEEDS SUMMARY CHART The Basic Needs Summary Chart is intended to evolve as students investigate a wide variety of living organisms throughout the unit. The chart can be a single class chart, students can complete it individually, or it can be done both individually and as a whole class. However it is completed, it is recommended that students be guided to reflect on their investigation experiences and use the chart to look for similarities and differences among organisms to build understanding of both the diversity and unity among living organisms.

Basic Needs Summary Chart

Investigation

Organism name and environment where it is found

How it grows

How it consumes nutrients

How it exchanges gases and where the gases are found

How it detects and responds to stimuli

How it reproduces

How it obtains water

How it eliminates waste

How many cells are in its body

What adaptations (behavioral and structural) make it better able to survive and reproduce?

Note: A new column is added to the chart for each organism encountered throughout the unit. An expanded version of this chart that can be printed on a transparency is included on the next page.



Basic Needs Summary Chart Investigation 2 3 3 5

Organism name and the environment where it is found

brine shrimp in water

Elodea in water

Paramecium in water

monocots and dicots on land

How it grows


How it exchanges gases and where the gases are found


How it reproduces



How many cells are in its body

What adaptations (behavioral and structural) make it better able to survive and reproduce?



Overview for Implementation

Investigation Key Science Content Concepts

Investigation 1 Living organisms need a particular environment in which to live

Some living organisms are dormant during a life stage Investigation 2 Living organisms occur on a lot of different size scales,

and—big or small––they all have the same characteristic needs

Investigation 3 All living organisms are made up of cells–some are multicellular and some are single–celled

Living individual cells may be part of an organism and not an individual organism

Investigation 4

Multicellular organisms are made up of differentiated cells that work together on a variety of levels

Immersion Investigation 4A Comparing Cellular Structures

Cells in multicellular organisms have needs and functions that are very similar to those of whole organisms.

Within cells are particular structures that function in ways that make it possible for them to carry on the many processes needed to sustain life.

Immersion Investigation 4B Human Cell Diversity

Some organisms are made of a collection of specialized cells that work together to meet the needs of the whole organism.

Some of those cells vary greatly in appearance and perform very different roles in the organism, yet they all originated from stem cells within the embryo of that organism.

Immersion Investigation 4C Cells in the Lab

Cells in multicellular organisms must meet the same characteristics of life as whole organisms.

Scientific investigations sometimes require scientists to maintain appropriate artificial environments for living organisms.

Investigations 5 and 6

Note: These investigations can be done at the same time, focusing on the 8 characteristics of living things throughout.

Seeds are dormant living organisms that begin to grow and develop under the right environmental conditions

The multicellular organisms, like plants, have differentiated cells that originate from a common cell type within the embryo

Stomates are specialized cells that plants need for gas exchange


INVESTIGATING THE DIVERSITY OF LIFE UNIT OVERVIEW Investigation 7 Plants have specialized structures, including flowers, to

accomplish reproduction

Plants that have seeds have a wide variety of dispersal methods that involve specialized structures

Investigation 8 Organisms have adapted structures to match their functions

Investigation 9 Organisms have adapted structures to match their functions

Immersion Investigation 9A Observing Crayfish and Cockroaches

All living organisms—single and multi-cellular—have to solve the same set of problems and do it in a variety of ways through physiological, behavioral and structural adaptations.

Scientific investigations involve collecting, analyzing and applying relevant evidence to support explanations.

Investigation 10 Scientists classify organisms by their similarities and differences




Immersion Units and the Science Inquiry Cycle Observations raise questions, investigations answer them, raise new questions, and start the process over again. While sixth grade students are not scientists, they can engage in every phase of the process of scientific inquiry. The terms used to describe the phases may sound too advanced for young students but we’ve found that even kindergarten students intuitively follow this cycle of inquiry. The call-outs in the inquiry cycle below show some possible age-appropriate responses.

Crayfish use their claws for defense by displaying and pinching. I know from my investigation and the book I read.

Crayfish seem to have special claws. How do they use them?

Learners communicate and

justify their proposed explanations.

Learner engages in scientifically

oriented questions

The book I read says that crayfish show their claws to display dominance and only attack when necessary.

I’ll put two crayfish in a tub together and record their behavior on a chart.

Learner gives priority to

evidence, which allows them to develop and evaluate

explanations that address scientifically oriented questions

Learners evaluate their explanations in light of

alternative explanations, particularly those reflecting

scientific understanding

Learner formulates explanations from evidence to address

scientifically oriented questions

Crayfish raise their claws but do not pinch them down on other crayfish or threats immediately.

Source adapted from the National Research Council. 2000: Inquiry and the National Science Education Standards. Washington D.C.: National Academy Press

Investigation 4A Snapshot Comparing Cellular Structures

1. Start students thinking about cells by asking them to brainstorm a list of where cells are found. Highlight the following points: • All living organisms are made up of cells, and cell types are

diverse. • Some cells are whole organisms, and some cells are made up

of masses of interacting and coordinating cells.

2. Pose the question, Since cells are alive, how do they meet the needs that all living things must satisfy to survive? • Have students choose one of the needs from the unit

organizer chart and predict if all organisms’ cells meet that need in the same way and explain how they think that need is met at the cellular level.

• Explain that you have some resource pages about cell structures to be used as evidence for explaining how cells meet their needs.

3. Have students work in pairs to complete the Student Page, What’s in a Cell? Assign a recorder in each group to record questions that come up about cells and their structures as they work. • Students can also complete the Organelle Function Chart to

organize the information in a different way to help look for patterns.

4. Discuss as a class students’ responses to the Student Page, What’s in a Cell? by asking about patterns observed and explanations developed about how cells meet their needs. • During the discussion, focus on helping students recognize the

pattern that single-cellular organisms tend to contain simpler structures because all of their life processes take place in one cell.

• The bacteria are the simplest organisms, and they contain no membrane-bound organelles. Still, they are very successful whole organisms.

• Though many organisms are dry-land organisms, their cells are aquatic—they need body fluids that bathe the cells and keep them moist (see FOSS pp. 128-131). Those that are aquatic organisms need specialized structures (water vacuoles) to pump out excess water.

• Explore additional resources such as the CELL: The Basic Unit of Life reading on page 27 of the FOSS resources book to gather evidence for students’ questions.

5. Complete the lesson by recording any unanswered questions for later and explaining that more investigations into cells will follow.

KEY CONCEPT(S) Cells in multicellular organisms have needs and functions that are very similar to those of whole organisms. Within cells are particular structures that function in ways that make it possible for them to carron the many processes needed to sust

y

ain life.

• elle Function

Chart

EVIDENCE OF STUDENT UNDERSTANDING The student will be able to: • Explain significant patterns

in the structures and functions of the organelles that are included in this lesson including: o complex functions tend to

be performed by complex structures

o bacteria are single-cell organisms that meet their needs with relatively simple cellular structures

TIME NEEDED 2 class periods MATERIALS For the class • FOSS Diversity of Life

CD(s) and equipment for group or individual access.

For each pair of students • 1 set of organelle

information cards For each student • 1 copy of the Student

Page What’s in a Cell? Comparing Cell Structures and their Functions 1 copy of the Student Page Organ

Diversity of Life Immersion Investigation 4A DRAFT 1

Student Page: What’s in a Cell? NAME______________________________________ 1. Since cells are alive, how do they meet the needs that all living things must satisfy to survive? In the space below, predict if all organisms’ cells meet one of the needs we are studying (you choose which one) in the same way.

• Chosen “need” to survive: _______________________________________ • Explain how you think that need is met at the cellular level.

2. Research and Recall (Work with a partner to compare two assigned types of cells) What structures are found in both types of organisms’ cells that you are comparing? Develop a Venn diagram to represent your evidence from the resources provided.

• Summarize in your own words what each cellular structure you listed does for the cell. 3. Extend: What structures are found in one but not the other type of organism that you are comparing? Using evidence, explain what you think accounts for this difference. 4. Analyze: Look at the list of structures and functions that you have listed, and share information about the other types of cells with the rest of your group.

• As a whole group, list all the patterns that you see in the information about cell structures. • Explain using evidence from the patterns you observed how the cells in these organisms meet

the need that you chose in #1. • Does this explanation match your prediction? Why or why not?

5. Self-Assess: Choose one cell structure that you learned about. What would you say to a third-grade student to explain why that cell structures are important for all or some cells?

SCALE Grade 6 Immersion Unit: Draft 10/31/06 Adapted from FOSS Diversity of Life

structure name Lysosomefound in typical plant cell

found in typical protist

found in typical fungus cell

found in typical bacterium

found in typical animal cell

function: reproduction

function: growth and differentiation

function: respond to environment

function: obtaining energy

function: maintaining water balance

function: waste elimination

descriptionLysosomes are filled with enzymes. These enzymes need to be kept separate from the rest of the cell or they could cause damage.

Cells use lysosomes to break down and recycle worn out organelles. Waste from these broken-down structures is disposed of through the cell membrane.

Plant cells typically have a central vacuole that does this job instead of a lysosome.

Single-celled organisms also use lysosomes to digest food particles that are brought into the cell.

function: gas exchange

Image

image source Diversity of Life - CD-ROM


structure name Mitochondrionfound in typical plant cell











descriptionThe mitochondrion processes sugars, producing energy for the cell and releasing simple chemicals into the cell cytoplasm.

The smaller picture next to the paramecium is a photograph made with a The lines in the mitichondrion in the picture are folds in the membrane. Mitochondrion are complex structures.

Mitochondrion are sometimes called the “power house.” Their job is to break apart food molecules to convert the energy to be used by cells.

Cells without any mitochondria have other ways to get energy through chemical reactions in the cytoplasm. Those processes do not generate as much energy for the cell to use as the processes that take place in the mitochonria


Image



structure name Nucleusfound in typical plant cell











descriptionThe nucleus regulates the cells’ processes. It contains genetic information that codes for how the cell functions, so it has a role in all cell functions.

The genetic information contained in the nucleus is essential for the cell and the organism to live. Can you see how the nucleus surrounds and protects that genetic information? It is like keeping a treasure map inside a plastic cover so that it doesn’t get damaged whil you are using it.

Unlike the treasure map in the example above, the genetic code must send special information to the ribosomes that are in the cytoplasm. It does this by sending out special chemical information to the ribosomes. The ribosomes follow the instructions from the genetic information by reading the chemical information sent out of the nucleus.

The nucleus is like a protective envelope that some cells have around their genetic information.


Image



structure name Water Vacuolefound in typical plant cell











descriptionWater vacuoles occur in some cells such as Paramecium. Water vacuoles gather water from the cytoplasm and transfer it out of the cell.

Living cells need water, but not too much water. The cell membrane keeps the inside of the cell separate from the outside environment. However, water can pass through the cell membrane. Depending on the environment where the cell lives, it may need to save water carefully or remove it. What kind of environment would you expect for a cell with water vacuoles? They are found in


Image



structure name Central Vacuolefound in typical plant cell











descriptionThe Central Vacuole is a large liquid-filled structure in plant and fungus cells.

The Central Vacuole stores water and waste products.


Image

image source


structure name Food Vacuolefound in typical plant cell











descriptionThe Food Vacuole is a baglike structure that stores nutrients. A lysosome merges with it to digest the nutrients and make them available to the cell.


Image



structure name Ribosomefound in typical plant cell











descriptionRibosomes assemble lots of different proteins in response to information that comes from the nucleus.


Image



structure name Golgi Bodyfound in typical plant cell











descriptionThe Golgi Body is a stack of membranes that modify and package proteins to be used in other parts of the body.


Image



structure name Chloroplastfound in typical plant cell











descriptionThe chloroplast is a structure in plant cells (and some protists) that uses energy from the sun, water, and carbon dioxide from the air to make food.

The food produced (through photosynthesis) is in the form of carbohydrates (sugars). These sugars enter the cell’s cytoplast where they are used for energy throughout the cell.


Image

image source cellsalive.com


structure name Cell Membranefound in typical plant cell











descriptionAll cells are surrounded by the cell membrane. It controls the movement of materials into and out of the cell.


Image



structure name Cell Wallfound in typical plant cell











descriptionThe cell wall is a rigid layer surrounding some types of cells, It gives shape and strength to plants, fungi, and bacteria.


Image

image source cellsalve.com


structure name Cytoplasmfound in typical plant cell











descriptionCytoplasm is the fluid contents of cells. If a cell has organelles, they float in the cytoplasm.cell


Image



structure name Peroxisomefound in typical plant cell











descriptionSome peroxisomes assists in converting fats into sugars that can be used for energy in the cell. Others help cells change harmful waste products that are produced when the cell processes foods into other substances that do not harm the cell. Inside a cell, a peroxisome looks similar to a lysosome in size and shape.


Image

image source Diversity of Life CD


structure name Endoplasmic Reticulumfound in typical plant cell











descriptionThe endoplasmic reticulum is made up of a group of membranes, It is found in the cytoplasm of a cell. The endoplasmic reticulum is connected to the nuclear membrane. It is responsible for the production or processing and movement of proteins. The endoplasmic reticulum sometimes looks rough because it has ribosomes on the surface. Sometimes the endoplasmic reticulum looks smooth because it has no ribosomes. Cells depend on the endoplasmic reticulum to process proteins that are needed to get energy needed and process the matter needed for growth and development and many other cell functions.


Image


Cell Structures Information Summary: Functions

Reproduction Growth & Differentiation

Respond to Environment

Obtaining Energy

Maintaining Water

Balance

Waste Elimination

Gas Exchange

Lysosome

Mitochondrion

Nucleus

Water Vacuole

Central Vacuole

Food Vacuole

Ribosome

Golgi Body

Chloroplast

Cell Membrane

Cell Wall

Cytoplasm

Peroxisome

Endoplasmic Reticulum

Investigation 9A.1 Snapshot KEY CONCEPT(S)

All living organisms have to solve the same set of problems and do it in a variety of ways through physiological, behavioral and structural adaptations. Scientific investigations involve collecting, analyzing and applying relevant evidence to support explanations.

EVIDENCE OF STUDENT UNDERSTANDING The student will be able to: • make and record accurate and

detailed observations of crayfish and cockroaches

• synthesize observations into a visual display of the data

TIME NEEDED 1 class period MATERIALS For the class • Overhead of Teacher Page:

Canid Tree

For each small group of students • crayfish in water • cockroaches

For each student • science notebook to record

observations • Copy of Student Page Crayfish

and Cockroach Venn Diagram • Copy of Student Page Crayfish

and Cockroach Observations

Observing Crayfish and Cockroaches 1. Share that today students will be investigating relatedness.

Explain that many things in nature are related. Show Teacher Page: Canid Tree, and explain that research tells us that dogs, foxes, and wolves are all related. They had a common ancestor a very long time ago. The fewer branches between each canid the closer they are related.

2. Explain that today they will investigate the relatedness of two different creatures and work on the question —How closely related are crayfish and cockroaches? Share that they will observe crayfish and cockroaches and record their observations in their science notebooks or Student Page: Crayfish and Cockroach Observations. They should also record any questions of their own that arise while making their observations.

3. Ask students what types of observations they think they could make. Generate a class list on the board, so students have an idea of what things to look for. These might include observations of specific structures, behaviors, or size.

4. Instruct groups to record 8-10 observations on one animal before moving to the next. Have students work in small groups to complete their observations and record their data. Provide them with appropriate vocabulary as needed. They may need to return to their first animal to make additional observations.

5. Put animals aside and have students work in their groups to complete Student Page Crayfish and Cockroach Venn Diagram.

6. Complete the lesson by recording any questions generated by students when observing the crayfish and cockroaches. Explain that they will be continuing to investigate these animals and may be able to investigate some of their questions.

7. Make sure students write down a response to the Predict question in their science notebooks. They need it to begin the next lesson.

REAPS R Why is it important to make detailed and accurate observations in science?

E What characteristics do cockroaches and crayfish have in common?

A What other animals do you know of that also have these characteristics?

P Remember how all human cells have a common ancestor, the stem cell? Do you predict that crayfish and cockroaches changed over a very long time from a common ancestor? Explain why you think that way.

S Switch student pages with a neighbor. Talk about what you see on the student pages that was done well and what could be improved on.


Teacher Page: Canid Tree

Fox

Domestic Dog Gray Wolf

Coyote

Jackals

Wild Dogs


Student Page: Crayfish and Cockroach Observations

Observe the crayfish and cockroach carefully and scientifically. Pay attention to even the smallest details. Record the structures and behaviors that you observe.

Crayfish Structures and Behaviors Cockroach Structures and Behaviors


Student Page Crayfish and Cockroach Venn Diagram

Review the data you recorded during your observations. List all the structures and behaviors crayfish and cockroaches share in the middle oval. List any that are unique to the crayfish in the left oval. List any that are unique to the cockroach in the right oval.

Shared Structures

and Behaviors

Cockroach Structures and Behaviors

Crayfish Structures and Behaviors


Investigation 9A.2 Snapshot KEY CONCEPT(S) All living organisms have to solve the same set of problems and do it in a variety of ways through physiological, behavioral and structural adaptations. Common descent is an important part of classifying organisms. Scientific investigations involve collecting, analyzing and applying relevant evidence to support explanations.

EVIDENCE OF STUDENT

UNDERSTANDING The student will be able to: • predict what a common

ancestor of crayfish and cockroaches might look like using observation data

• refine their prediction based on additional research data

TIME NEEDED 1 class period

MATERIALS For each pair of students • 1 copy of Student Page

Common Ancestor

For each student • science notebook to record

predictions • 1 copy of Student Page The

Arthropods • 1 copy of Student Page

Arthropod Differences • note-card

Comparing Crayfish and Cockroaches 1. Engage students in discussing their responses to the Predict

question from the previous lesson—Do you predict that crayfish and cockroaches have a common ancestor? Explain why you think that way with a partner. Encourage them to be scientific and challenge each other for evidence that supports their thinking.

2. Share that research does suggest crayfish and cockroaches share a common ancestor, despite the many differences in the two animals. Ask the pairs of students to develop a prediction of what that ancestor might look like on Student Page Common Ancestor. Remind them to rely on the common characteristics section of their Venn Diagrams for data, and label the characteristics.

3. Share that you have an article that will provide them more evidence for explaining what the common ancestor might look like. Allow students to read and complete Student Page The Arthropods. Allow the pairs of students to revise their common ancestor drawing, as needed.

4. When students have finished, ask a student who originally did not predict that the crayfish and cockroaches had a common ancestor to share their evidence for thinking that way. Often their evidence was the drastic differences between the two animals. Explain that these differences are interesting to scientists, too. Allow students to explore the differences between crayfish and cockroaches by working through Student Page Arthropod Differences.

5. Ask students to share with a neighbor their prediction from Student Page Arthropod Differences that explains the specialization seen in crayfish and cockroaches . Then, call on a few students to share their predications with the class. Call attention to any predictions that suggest that the environment is related to the specialization, but avoid affirming as correct.

6. Explain that in the next class students will explore more about specialization. They will do an investigation with one of the arthropods to determine how their environments may relate to specialization. This might help them better explain if the environment has something to do with specialization.

7. Ask each student to write their name on a note-card and record if they would prefer to investigate crayfish or cockroaches.

REAPS R How long ago did the common ancestor of all arthropods live? E How has one of the arthropods on your Student Page The Arthropods specialized from the

common ancestor of all arthropods? A Choose one crayfish or cockroach specialized structure or behavior and explain how it helps

them meet the their survival needs? P How do you think specialized structures and behaviors benefit crayfish and cockroaches? S Why might the scientists’ description of the common ancestor be more accurate than yours?


Student Page Common Ancestor

Do cockroaches and crayfish share a common ancestor? Research done by scientists suggests they do. What does your research tell you? Review the notes you took while observing. Study your Venn Diagram. If crayfish and cockroaches share a common ancestor, what might it look like? What characteristics might it have?

List the characteristics that you predict the common ancestor of crayfish and cockroaches might have.

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• Prediction Make a prediction for what their common ancestor might look like. Remember to use your data as evidence. You can describe the ancestor in words or you can draw what you think it looks like. If you draw the ancestor, make sure you label the characteristics you chose to show.

• Justification What made you choose the characteristics you did for the common ancestor? Explain your thinking.

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Student Page The Arthropods

What are Arthropods? Arthropods are diverse and abundant, and have been that way for a long time. The first arthropods roamed the earth 500 million years ago. One reason, scientists think this from studying fossils. The oldest arthropod fossils are 500 million years old.

The crayfish and cockroaches you observed belong to the same group of animals—the arthropods. Scientists group animals in the same group when they have many similarities. Crayfish and cockroaches are both arthropods, what else do think is an arthropod?

It is hard to imagine that many years. To give you an idea, let’s think about the dinosaurs. The dinosaurs first walked the earth only about 225 million years ago. The arthropods had already been around for 275 million years. The first arthropod fossils are 275 million years older than the first dinosaur fossil. These early arthropods are the ancestors of today’s arthropods.

What arthropods do you know of? Make a list of animals you think are arthropods.

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_____________________________________ Today’s arthropods still share many similar characteristics with their ancestors. However, they are not exactly like their ancestors. Today’s arthropods have many differences in appearance and behavior.

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_____________________________________ _____________________________________ Where do arthropods live?

Arthropods are found in many, many different types of environments. Scientists have discovered them living on the land, in the soil, in the sky, in the oceans, and in freshwater. Arthropods live in every region on Earth, including tropical regions, temperate regions, and even artic regions.

How many arthropods are there? Arthropods are the most diverse type of animals on Earth. There are more species of arthropod than any other type of animal. Just think about the two types you observed in class. There are at least 4000 species of cockroach, and over 540 species of crayfish! Scientists estimate that there are over 10 million different species of arthropods. Arthropods are also the most abundant. There are more individual arthropods than any other type of animal. How long have arthropods existed? Diversity of Life Immersion Investigation 9A DRAFT 7


From “Understanding Evolution: Your one-stop source for information on evolution.“

What characteristics do all arthropods have in common? How do these characteristifor the crayfish and cockroMake a list of the characteristics you think all arthropods share.

Review your prediction of the ancestor on Student Page Commcharacteristics? How might you

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cs compare to your prediction aches’ common ancestor?

crayfish and cockroaches’ common on Ancestor. Does it show these improve your prediction?

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What does the research say about the common ancestor of all arthropods? Scientists studied the oldest arthropod fossils. These 500 million year old fossils have provided evidence for explaining what the common ancestor of all arthropods looked like.

The oldest arthropods showed bilateral symmetry. Organisms that have bilateral symmetry are basically the same on both sides. This means if you cut them in half lengthwise, both sides would be very similar. Butterflies, humans, frogs, lizards, birds, and fish all show bilateral symmetry.

The oldest arthropods also had an exoskeleton and many segments. They also probably had at least 10 pairs of jointed limbs. The limbs appear to be very similar in their shape and size. Unfortunately, scientists can’t observe the behavior of fossils, so its hard to be sure what the limbs were used for. The limbs look like the walking legs seen on living arthropods. The oldest arthropod lived under water and breathed with gills.

How does it compare to your prediction? Compare your prediction from “Student Page: Common Ancestor” to what scientists believe the common ancestor of all arthropods looked like.

• What characteristics are similar?

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• What characteristics are different?

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Student Page: Arthropod Differences

How similar are arthropods? Arthropods have many similar characteristics. This is because they share a common ancestor. All arthropods have :

• jointed limbs • hard exoskeletons • many pairs of limbs • segmented bodies • bilateral symmetry

How different are arthropods? Arthropods do have many characteristics in common, but they have many differences. Think back to your Crayfish and Cockroach Venn Diagram. What kinds of differences do they have? Look back at your list of arthropods on The Arthropods. What kinds of differences do they have? Let’s just think about limbs for now. All arthropods have many pairs of jointed limbs, but what those limbs look like and what they are used for vary. Crayfish have specialized front limbs for defense. Walking sticks have limbs that look like tree twigs for camouflage. Bees have specialized legs for holding pollen. Centipedes have one pair of legs on each body segment. Their first pair of limbs have been modified into fangs that inject venom into their prey. Can you think of other specialized limbs that arthropods have?

How can there be so many differences? Research tells us that arthropods all descended from one ancestor. Over time arthropods have changed. They all have some of the same characteristics, but many things are different. Today’s arthropods have body parts and behaviors that do specific jobs very well. When an organism has something that does a specific job very well scientists call that specialization (special-lie-zay-shun). Arthropods have specialized body parts and behaviors. What is specialized on crayfish and cockroaches? ______________________________________________________

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How do specialized structures and behaviors help crayfish and cockroaches meet their basic needs? Make a prediction and include your evidence for thinking that way.

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KEY CONCEPTS Closely related organisms that live in different environments have different adaptations Scientific investigations involve collecting, analyzing and applying relevant evidence to support explanations.

EVIDENCE OF STUDENT UNDERSTANDING The student will be able to: • generate, investigate,

and explain a scientific question that provides insight on arthropod adaptations

• identify benefits and costs of specialization

TIME NEEDED 1 class period MATERIALS For the class • Teacher Page: Basic

Habitat Design For each group • supplies for

investigation (crayfish or cockroach, soil, water, pvc pipe pieces, gravel, sticks, 6 liter containers, timers, measuring devices, etc.)

For each student • 1 copy of the Student

Page Arthropod Investigations

Investigation 9A.3 Snapshot Investigating Crayfish and Cockroach Behavior

1. Remind students that during the last class they made predictions about how do specialized structures and behaviors benefit crayfish and cockroaches, and that there was an idea that they helped them survive in their environment. Today, they will act like scientists as they do an investigation to collect evidence about that idea, and allow them to make a more scientific explanation.

2. Provide students with Student Page Arthropod Investigations. Allow students time to observe their organism. Then, make a class list of what could be changed about the environments (density of organisms, physical makeup, type/amount of water, threats, shelter, food, etc.). Allow students to complete their investigation and consider their data when responding to the question—How do specialized structures and behavior benefit crayfish and cockroaches?

3. At the end of the investigation, students should identify that specialized structures and behaviors seem help organisms survive and meet their basic needs. For example, the crayfish’ specialized backward scoot protects them from threats or the cockroach’s specialized bristled feet allow them to climb branches.

4. Ask students to think back to the common ancestor of the arthropods—Could the common ancestor respond as well to the crayfish’s environment as the crayfish? No the common ancestor had no claws to defend against threats. Could it respond as well to the cockroach’s as the cockroach? No, the common ancestor had gills and could only breath under water.

5. Ask students to think about the opposite question, too—What are the costs of specialized structures and behaviors? The specialized front limbs on the crayfish may be useful from protection, but they are no longer useful for walking. The lack of gills on the cockroach may be useful for living on land, but it can’t survive being knocked in a stream.

6. Encourage students to use their investigation to generalize about arthropods. Remind them that there are many more arthropods, and that each has different specialized structures and behaviors from that common ancestor. Ask students to do a Think-Pair-Share on—What might account for the diversity of specialization in arthropods worldwide?. Students should cite evidence that arthropods live in every region of the world. If the specialization was related to their environments, it would make sense that the specialization varied, too.

7. Explain that scientists call structures and behaviors that are specialized for one particular environment adaptations. They help organisms survive in their environment. Finally, ask students to generalize about other organisms. Have them talk with a neighbor about whether they would expect other organisms, like bats, fish, birds, and slugs, to have adaptations for the environments they live in, and why. Have a few students share their ideas and evidence for thinking so with the class.

Student Page Arthropod Investigat

Diversity of Life Immersion Investigation 9A DRAFT

ions

12

Which arthropod will you investigate?

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What do you think is specialized about your arthropod? List the structures and behaviors you believe are specialized about your arthropod. Think back to your observations and what you know about the common ancestor of all arthropods.

____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________

How might a scientists investigate a living thing and its environment? When scientists have a question and an idea about the answer, they often do investigations to collect more evidence. This helps them gather more evidence about their idea. Our class is wondering—How do specialized structures and behaviors benefit crayfish and cockroaches? We also have an idea about the answer—it may be related to their ability to survive in their environments. Like scientists we can do an investigation to collect evidence for explaining our question.

Scientists can’t always investigate organisms in their natural environments. Often, they must remove organisms from their natural homes. When scientists do this, they create a similar environment for the organism to live in. They also try to avoid harming the organism.

How do you get started? Today, you will behave like scientists and start with observations. Observe your crayfish or cockroach for about 10 minutes. Record your observations of how it responds to or interacts with its environment. What structures does it use to respond? How does it behave?

What goes into a scientific investigation? 1. Start with your observations and what you already know about crayfish and cockroaches!

Use that knowledge to ask a question. Ask something that will tell you about how arthropods use their specialized structures and behaviors to respond to their environment.

For example:

• If we added _______ to the environment, how would the arthropod use its specialized structures or behaviors?

• If we removed ______ from the environment, how would the arthropod use its specialized structures or behaviors?

2. Decide what evidence you will collect, and how you will collect it. For example, you might record things like the arthropod’s : • location every minute on a diagram of the

environment • behavior before and after adding something

to the environment 3. Setup your investigation and collect your data. 4. Use your evidence to explain your question.. Be sure to think about how the specialized structures and behaviors of crayfish and cockroach benefit them. For example, • Crayfish use ___________ (specialized

structures/behaviors) to ________ . We know this because____________. The other reason we think this way is _____.

Investigation 4C Snapshot Cells in the Lab 1. Share with students that studying cells is something that

interest a lot of scientists. Explain to students that there are scientists all around the world studying cells in laboratories. Ask students what reasons they know of that for scientists studying cells in a lab.

2. Explain that whatever reasons scientists want to study them for, they usually require living cells to study. Since the cells are not in their natural environment, the scientists must maintain appropriate environments for them to survive in. Ask students to do a Think-Pair-Share on What would the scientists need to keep in mind about cells if they wanted them to survive in the lab? Be sure that after the Think-Pair-Share students have an accurate class list of the needs of living things. See Teacher Page: Cells in the Lab.

3. Handout Student Page: Cells in the Lab. Have students copy the class list into the left-hand column.

4. Share that you have a video of scientists maintaining living cells in a lab. They need to watch the video and try to identify what things the scientists are doing to maintain each of the needs that they listed on their student page.

5. After the video, allow students to complete the right-hand column of the student page. They can draw and label or describe what they saw the scientists doing that they believe met this need for the cell.

6. Collect student work and assess their ability to apply their knowledge of the characteristics of life to the scientists work.

KEY CONCEPTS Cells in multicellular organisms must meet the same characteristics of life as whole organisms. Scientific investigations sometimes require scientists to maintain appropriate artificial environments for living organisms.

EVIDENCE OF STUDENT UNDERSTANDING The student will be able to: • list the characteristics

that cells need for survival.

• draw or describe the ways that scientists maintain living cells in a lab

TIME NEEDED One class period MATERIALS For the teacher • Copy of Teacher Page:

Cells in the Lab For each student • Copy of Student Page:

Cells in the Lab

REAPS R Name something the scientists did in the lab and what need it meet for the cell? Students should

cite specific sections of the video.

le cells would.

E If the scientists were working with muscle cells from a rat, would you expect them to perform the same tasks? For the most part yes, muscle cells and cells from other animals need similar things. However, they might need different nutrients and concentrations of solutions.

A How might maintaining a rat muscle cell compare to maintaining a rat for a scientific investigation? The same needs would need to be met, but rats would need a very different environment than rat musc

P What do you think scientists would need to do to maintain plant cells in a lab? Predictions will be based on prior knowledge. Plants cells would need similar maintenance, but would need different temperatures and types and concentrations of nutrients. They would also need light.

S How does your Student Page compare to your neighbors?

Diversity of Life Immersion Investigation 4C DRAFT

Teacher Page: Cells in the Lab What would the scientists need to keep in mind about cells if they wanted them to survive in the lab?

What did the scientists do in the video for this need?

How it grows


How it exchanges gases


How it reproduces




Student Page: Cells in the Lab

What would the scientists need to keep in mind about cells if they wanted them to survive in the lab?

What did the scientists do in the video for this need?


Investigation 4B Snapshot KEY CONCEPTS

Some organisms are made of a collectispecialized cells that work together to meet the needs of the whole

on of

organism. Some of those cells vary greatly in appearance and perform very different roles in the organism, yethey all originated from stem cells within the

t

sm. DENT

T • trast

•

and

ing specialized cell

riods

• ce CD tion

e

• ent Page: Cell

• nt Page: Human Cells

embryo of that organiEVIDENCE OF STU

UNDERSTANDING he student will be able to:

Compare and condifferent types of specialized human cells. Explain that stem cells are the common ancestor of all a human’s cellsthat they differentiate productypes.

TIME NEEDED Two class pe

MATERIALS For each group

access to Unit Resourwith cell informa

• prepared slid• microscope • poster paper/markers

For each student Copy of StudConference Copy of Stude

Human Cell Diversity 1. Remind students that they have seen many types of cells from plants

and animals. Share with students that they are going to have an opportunity to investigate the cells that make up parts of the human body. Ask students to draw what they think a cell in the human body might look like. They can draw any cell in the human body they want. Refrain from listing types of cells. This is an effort for them to think about what they know already and for you to assess their current understandings about the cells of the human body.

2. Explain that they will work in groups of 3-4 to learn about one type of human cell. Then, they will present their findings at a class conference. Ask students to brainstorm how they think scientists might behave at a conference. Provide students with Student Page: Cell Conference and make sure they understand the assignment. Assign each group one of the seven cell types from Student Page: Human Cells. Give each group the CD, a prepared slide, and about 20 minutes to do the research. Another 20 minutes can be spent on the posters and preparing for their presentation.

3. When groups have finished collecting their data, begin the presentations. Encourage the rest of the class (the conference attendees) to behave like scientists, and carefully record the other groups data on their student page for comparing and discussing later.

4. At the end of the presentations, ask students what they noticed about human cells. Prompt students to compare the different types of cells and to compare the cellular structure of humans to one-celled organisms. Model being intrigued by the enormous diversity in human cells. Ask students to predict—What might the cell that is the common ancestor of all the cells in your body be like? Have them make a drawing or describe what features they think the common ancestor of all their cells would have.

5. Explain that scientists are interested in where these very different types of human cells come from, too. They have discovered that stem cells play a key role in the process. Allow students to study the CD section for stem cells either in groups or show it on a projector for the whole class. Make sure students understand that their stems cells are the common ancestor for all the cells in their bodies. Stem cells differentiate and change into the other types of cells.

REAPS R What is the common ancestor of all the specialized cells in your body? By the end of this lesson,

students should know that their stem cells were the common ancestor of all the cell in their bodies.

E What similarities do the different types of human cells have? What differences? Students should base their answers off the data recorded on Student Page: Human Cells.

A Which of the 7 characteristics of life do red blood cells help humans meet? How about sperm cells? Red blood cells help with gas exchange. Sperm cells help with reproduction. Other specific cells may help meet one or many of the characteristics of life.

P The plant cells in Elodea looked basically the same. They were not very specialized. Would you expect celery, grass, or beans to have any specialized cells? Predictions will be based on prior knowledge, and may not identify that these plants do indeed have specialization. Root, leaf, and stalk cells are all specialized.

S How does your drawing of what a human cell might look like from the beginning of this lesson compare to what you now know about human cells? How is it similar and different?

Diversity of Life Immersion Investigation 4B DRAFT

Student Page: Cell Conference What is a scientific conference like? Part of being a scientist is learning from others. New research is built on the previous research done by others. Conferences are a place where scientists come together to exchange information. Scientists often make oral presentations about their work at conferences. They may use a poster that shows some of their most important points. They also use notes to explain the details about their work.

Other scientists attend the conferences to listen, learn, and ask questions. They try to use what others know to improve their work. What will our Cell Conference be like? In our Cell Conference, you can behave like a scientist. One group will present their cell research. The rest of the class will be “conference attendees”. Like scientists at conferences, you will be listening, learning, and asking questions of the group that is presenting. It is very important that you record the data the other groups present.

Your future research will be built on the information they share.

What do you need to present? You need to make a poster with:

the name of your cell • • •

a simple, large sketch of your cell a brief description of the cells function.

You also need to complete the column on Student Page: Human Cells for your type of cell. This will be your notes. At the conference, start by sharing your poster. Then, explain the rest of the details about your cell so that conference attendees can record the data on their Human Cells page. What about presenting in a group? Sometimes at scientific conferences, groups of scientists present together. This requires coordination and planning. They have to know who is going to say what, and in what order.

Since you are presenting with a group, you will need to do the same things. Decide what role each person will take. • Who will explain the drawing? • Who will explain the function? • Who will explain details about your cell? • Who will ask the conference attendees if

they have any questions? You should work as a team to try answer any questions the conference attendees have. Keep in mind that you have not been researching your cell long, and may not know all the answers.

Diversity of Life Immersion Investigation 4B DRAFT

Life Immersion Investigation 4B DRAFT

Cell White Blood Cell

Red Blood Cell

Sperm Neuron Heart MuscleCell

Ciliated Cell

Egg Cell

Function

Looks like

Size

Can it move?

Lifespan

Interesting facts about organelles

One other interesting fact

Student Page: Human Cells

Diversity of

structures of life - wisconsin fast plants® investigations for... · foss diversity of life unit,...

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