Chapter 1: A View of Life

Characteristics of Life

Living Things are organized Small molecules form

larger molecule within a cell

Some organisms are unicellular

Plants and animals are multicellular

In multi cellular organisms

Cells combine to form tissues

Tissues combine to form organs

Organs combine to form organ systems

Organ systems make the organism

Living Things Acquire Materials and Energy

Energy is the ability to do the work it takes to maintain life

Metabolism is all the chemical reactions that occur in a cell

Living Things Acquire Materials and Energy Continued

Ultimate source of energy is the sun Plants, bacteria, and

algae can convert light energy into chemical energy through photosynthesis

For metabolic processes to continue, there must be a stable tempeature, moisture level, pH, and other factors This is called homeostasis

Living Things Respond

Organisms respond to their environment This is called behavior

Living Things Reproduce and Develop

All organisms can reproduce, or make more organisms like itself Can be asexual or

sexual

Living Things Have Adaptations

Adaptations are modifications that makes an organisms suited for its way of life

Evolution: A Core Concept in Biology

Diversity of Life

Categories of classification From most specific to

least specific Species, Genus,

Family, Order, Class, Phylum, Kingdom, Domain

Scientific Naming

Species are described using the genus and species

The genus is capitalized and the species is lower-case, the whole name is italicized

Homo sapiens Occasionally, the genus will

be abbreviated with the first letter and a period if the genus is considered obvious

T. rex

Domains

Bacteria, Archaea, Eukarya Bacteria and Archaea

are prokaryotes Kingdoms

In Eukarya there are four Kingdoms

Animalia, Protista, Fungi, Plantae

Science: A Way of Knowing

Observation

First step of the scientific method

Collected with the senses

Hypothesis

Arrived at through inductive reasoning by looking at a phenomena at explaining it using all the information avaiable

Must be testable

Experiment/Further Observation

What is an experiment

Designed test of a hypothesis

Experimental design is important to make sure only one variable is being tested

This can be accomplished by having an experimental group and a control group.

Experiment/Further Observation Continued

Models can be used to represent complex systems in a way that is easy to comprehend Global climate is often

model to bring it to a reasonable level

Data

Data are the result of an experiment Can be qualitative or

quantitative Quantitative is usually

preferred because it can be compared

Conclusion

Derived from the data States whether a

hypothesis is supported or not

Experiments can never prove anything, but can only disprove the null hypothesis

Scientific Theory

Accepted explanations for observed phenomena Based on several

experiments “Best explanation so

far” If theory becomes

accepted for a very long period of time it can become a principle or law

Science and Bioethical Issues

Biodiversity Maintaining

biodiversity is important for ecosystems

Extinction Species going extinct

is a concern