Bellwork

• Sit down.

• Clear your desk.

• You have 10 min. to do the quiz.

If you are not prepare in 3

minutes for the quiz. Its going to be a zero on your

grade.

Cell and Life ProcessesEssential Question: What are cells made of?

Levels of OrganizationAfter this lesson, students will be able to:

• Distinguish among the levels of organization in many-celled organisms.

To keep in mind:

• What are the levels of organization in an organism?

Click Print for new Skin

You’ve probably seen text or images printed by an ink-jet printer. Imagine using the same technology to make skin. A research team, headed by Professor Brian Derby, has adapted ink-jet printers to print human cells. The research team hopes to use this technology to build tissues, such as skin to help treat burn victims. A small number of healthy cells are taken from the patient and used to grow many more cells. These cells are placed in a liquid that serves as the “ink.” As the liquid goes through the printer, the cells are seeded onto a piece of plastic that provides a base for more cells to grow. The new tissue should fit the wound perfectly. This technology can print more than one type of cell at a time, just as printers can use more than one color ink. It can also be used to build three dimensional objects. Researchers hope to be able to print not just skin, but bone, cartilage, and, someday, maybe entire organs!

Click Print for new Skinhttps://www.bing.com/videos/search?q=ink-jet+printers+to+print+human+cells.&FORM=HDRSC3#view=detail&mid=AD59044C14A4BA8A432FAD59044C14A4BA8A432F

What are the levels of organization in an organism?

• Organisms, or living things, are made of tiny particles that can join together, making larger structures.

• The levels of organization in an organism from smallest to largest are atoms, elements, molecules, compounds, cells, tissues, organs, and organ systems.

What are the levels of organization in an organism?

• Every living and nonliving thing is a type of matter.

• Elements make up matter.

• An element is any substance that cannot be broken down into simpler substances.

• Important elements in the body include carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus, calcium, and sodium.

• The smallest unit of an element is a particle called an atom.

• Any single element is made up of only one kind of atom.

Levels of Organization

ElementsThe colored spheres represent atoms. Which examples represent the same element?

What are the levels of organization in an organism?

Molecules and CompoundsCarbon dioxide is a compound. So is water.

Levels of Organization

What are the levels of organization in an organism?

• A cell is the basic unit of structure and function in living things.

• If a living thing has only one cell, it is called unicellular.

• Plants and animals are multicellular, which means “made of many cells.”

• All cells in a multicellular organism must carry out key functions to survive.

• Specialized cells may perform specific functions that benefit the entire organism.

• Specialized cells may differ in structure as well as in function.

What are the levels of organization in an organism?

• In multicellular organisms, cells are organized into tissues, organs, and organ systems.

• A tissue is a group of similar cells that work together and perform a specific function.

• An organ is made of different kinds of tissues that function together.

• A group of organs that work together and perform one or more major functions is an organ system.

• Organ systems work together in an organism.

• The level of organization becomes more complex from cell to tissue to organ to organ system.

Levels of Organization

Levels of Organization

Living things are organized in levels of increasing complexity. Complete the missing terms to show the patterns of organization of organisms from simple to complex.

Cell and HomeostasisAfter this lesson, students will be able to:

• Identify cell processes that maintain homeostasis, such as extracting energy from food, getting rid of water, and reproducing.

To keep in mind:

• How do cells maintain homeostasis?

Has your thinking ever felt fuzzy from lack of sleep?

New research suggests that brain cells function better when well rested. Tests conducted with fruit flies and rats showed that proteins build up in the brain during wakeful times and decrease during sleep. These proteins take up space between brain cells and use energy. Researchers think sleep helps “clean house,” saving energy and space and restoring balance in the brain. In a way, sleep refreshes the brain and prepares it to learn more effectively during the day.

How do cells maintain homeostasis?

• Homeostasis is the maintenance of internal stable conditions that are necessary for life functions.

• Entire organisms maintain homeostasis. So do individual cells.

• In all cells, the processes that help maintain homeostasis include getting and using energy from food and removing wastes.

How do cells maintain homeostasis?• Most organisms get energy from cell processes that break

down foods.

• During cellular respiration, cells break down glucose molecules in the presence of oxygen, releasing energy.

• Waste products of this process include carbon dioxide and water.

• Animals and some other organisms get food for energy by eating other organisms.

How do cells maintain homeostasis?• Unlike animals, plants and some other organisms can make

their own food.

• The process by which cells capture the energy in sunlight and convert it to energy stored in food is called photosynthesis.

• Often, the foods produced in photosynthesis are glucose or other sugars.

• The raw materials for photosynthesis are carbon dioxide from the air and water. Oxygen leaves the cell as a waste product.

Photosynthesis & Respiration

What is Photosynthesis?

The process of photosynthesis is a chemical reaction.

It is the most important

chemical reaction on our planet.

What is the Equation for the Chemical Reaction of Photosynthesis?

What is the equation for the chemical reaction of photosynthesis?

What is the equation for the chemical reaction of photosynthesis?

Six molecules of carbon dioxide react with six molecules of water to form 1 molecule of

glucose and six molecules of oxygen.

Describe Photosynthesis

Describe Photosynthesis• The process of changing light energy to chemical energy

• Energy stored as sugar

• Occurs in plants and some algae

• Plants need light energy, CO2, and H2O

• Takes place in the chloroplasts, using chlorophyll, the green pigment in plants

What happens during photosynthesis?

What happens during photosynthesis?

• Plants capture light energy and use that energy to make glucose

• Sunlight provides the energy needed by chlorophyll to change molecules of carbon dioxide and water into glucose

• Oxygen is also released in this reaction

What happens during photosynthesis?

• Carbon dioxide enters the leaf through holes called stomata

• CO2 combines with the stored energy in the chloroplasts through a chemical reaction to make glucose

• The sugar is moved through tubes in the leaf to the roots, stems and fruits of the plants

• Some of the sugar is used right away by the plant for energy; some is stored as starch; and some is built into plant tissue

Why is this important to us?

Why is this important to us?

We cannot make our own food (glucose, energy), we must get our food from plants.

Plants are the first step in the food chain.

Why is this important to us?

The oxygen released during photosynthesis is necessary for all living things.

What is Cellular Respiration?

What is Cellular Respiration?

The release of chemical energy for use by cells.

What is Cellular Respiration?Once the energy that was in sunlight is changed into

chemical energy by photosynthesis, an organism has to transform the chemical energy into a a form that can be used by the organism.

This process is cellular respiration.

Describe Cellular Respiration

Describe Cellular Respiration• The breakdown of glucose molecules to release

energy

• Takes place in all living things

• Is a step by step process

What is the chemical equation for cellular respiration?

What is the chemical equation for cellular respiration?

How do cells maintain homeostasis?• To maintain homeostasis, materials such as food and oxygen must move into

cells.

• At the same time, waste materials must exit.

• Materials that move in or out of a cell must cross a structure called the cell membrane.

• The cell membrane surrounds a cell, separates it from the outside environment, and controls which substances enter and leave.

• One way materials move across the cell membrane involves collisions of molecules.

• These collisions push molecules away from one another in a process called diffusion.

• During diffusion, molecules move from an area of higher concentration to an area of lower concentration. Eventually, the molecules spread evenly throughout a space.

Passive Transport

• When a cell uses no energy to move particles across a membrane passive transport occurs

• Particles go DOWN their concentration gradient.

• Diffusion & osmosis are passive transport.

Concentration gradientPlasma membrane

Osmosis: Diffusion of Water

• Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration.

• In a cell, water always moves to reach an equal concentration on both sides of the membrane.

Concentration gradientConcentration Gradient - change in the concentration of a

substance from one area to another.

Diffusion

[High] [Low]

concentrated, high energy molecules

diffuse, low energy molecules

Osmosis: Diffusion of Water

• The diffusion of water across a selectively permeable membrane is called osmosis.

• Regulating the water flow through the plasma membrane is an important factor in maintaining homeostasis within a cell.

Osmosis• Osmosis is the movement of WATER across a semi-permeable membrane

• But over time, the water moves across the semi-permeable membrane and dilutes the particles.

What controls osmosis?

• Unequal distribution of particles, called a concentration gradient, is one factor that controls osmosis.

BeforeOsmosis

AfterOsmosis

Selectively permeable membrane

Water molecule

Sugar molecule

Osmosis: Diffusion of Water

• Most cells whether in multicellular or unicellular organisms, are subject to osmosis because they are surrounded by water solutions.

Cells in an isotonic solution

• isotonic solution-

• (= concentrations)

• the concentration of dissolved substances in the solution is the same as the concentration of dissolved substances inside the cell.

H2OH2O

Water Molecule

Dissolved Molecule

Cells in an isotonic solution

• water molecules move into and out of the cell at the same rate, and cells retain their normal shape.H2O

H2O

Water Molecule

Dissolved Molecule

Cells in an isotonic solution

• A plant cell has its normal shape and pressure in an isotonic solution.

Cells in a hypotonic solution

• hypotonic solution: dilute solution thus low solute concentration

• In a hypotonic solution, water enters a cell by osmosis, causing the cell to swell.

H2O

H2O

Water Molecule

Dissolved Molecule

Cells in a hypotonic solution

• Plant cells swell beyond their normal size as pressure increases. (plants prefer this –it makes the leaves firm)

Cells in a hypertonic solution

• hypertonic solution:

concentrated solution, thus a high solute concentration

In a hypertonic solution, water leaves a cell by osmosis, causing the cell to shrink

H2OH2O

Water Molecule

Dissolved Molecule

Cells in a hypertonic solution

• Plant cells lose pressure as the plasma membrane shrinks away from the cell wall. PLASMOLYSIS

• Cytoplasm is a solution of water and solids (solutes dissolved in the water).• Water moves into and out of cells because of the

different concentrations of the solutes.• Different kinds of cells react differently depending on

the solution they are in.• Below are examples of red blood cells in different

types of solutions and shows what happened to the red blood cells.

OSMOSIS and DIFFUSION

Active Transport

• active transport :Movement of materials through a membrane against a concentration gradient and requires energy from the cell.

Concentration gradient

Plasma membrane

Carrier proteins

Cellular energy

Cellular energy

Transport of Large Particles

• Endocytosis is a process by which a cell surrounds and takes in material from its environment.

– The material is engulfed and enclosed by a portion of the cell’s plasma membrane.

– resulting vacuole with its contents moves to the inside of the cell

• Exocytosis is the expulsion or secretion of materials from a cell.

ExocytoseEndocytosis

Cells and Homeostasis

Energy From FoodFlorida’s orange crop comes from the energy captured in photosynthesis. The 2008–2009 crop totaled 162 million boxes. Which process applies to each organism?

Cells and Homeostasis

DiffusionSome materials move across the cell membrane by way of diffusion. Show the overall direction that molecules will travel as a result of diffusion.

How do cells maintain homeostasis?• All multicellular organisms grow during some part of their lifetimes.

They also have structures that wear out or become injured and must be replaced.

• Growth and repair can occur because cells reproduce, or make more cells.

• Cell division is a process in which one cell splits into two new cells that are genetically identical to the original cell.

• Through cell division, your body replaces damaged skin cells and worn out blood cells.

• Reproduction of cells is one of the processes that helps multicellular organisms maintain homeostasis.

• You grow as your body produces more muscle cells, bone cells, and other kinds of cells. Growth and repair help your body maintain homeostasis.