Chapter One

Biology: The Study of Life

I. Biology is the study of Life.

II. What do Biologist do?

• A. Study diversity of life

B. Research Diseases

C. Develop Technologies

D. Improve Agriculture

E. Preserve the Environment

III. Characteristics of Life

A. Anything that has or once had all the characteristics of life is known as an organism.

B. Characteristics Include:

1. Composed of one or more cells: •Single-cell organisms have everything they need to be self-sufficient. •In multicellular organisms, specialization increases until some cells do only certain things.

2. Displays Organization:

• Both molecular and cellular organization.

• Living things must be able to organize simple substances into complex ones.

• Living things organize cells at several levels:

• Tissue - a group of cells that perform a common function.

• Organ - a group of tissues that perform a common function.

• Organ system - a group of organs that perform a common function.

• Organism - any complete living thing.

3. Grows and Develops

a. What is Growth?

(1) Cell division - the orderly formation of new cells.

• (2) Cell enlargement - the increase in size of a cell.

• b. What is Development?

(1) all the changes that occur in life.

4. Reproduces:

• Reproduction is not essential for the survival of individual organisms, but must occur for a species to survive.

All living things reproduce in one of the following ways:

• Sexual reproduction - Producing offspring by the joining of sex cells.

• Asexual reproduction - Producing offspring without the use of gametes.

5. Responds to stimuli:

• Living things will make changes in response to a stimulus in their environment.

6. Require energy:

• Living things take in energy and use it for maintenance and growth.

7. Maintains Homeostasis

• Organisms keep internal conditions stable.

8. Adaptations evolve over time:

• Adaptations are traits giving an organism an advantage in a certain environment.

• Variation of individuals is important for a healthy species

• Gradual accumulations of adaptations over time is evolution.

IV. The Nature of Science

• A. Science is a body of knowledge based on the study of nature and its physical settings.

• B. Theory-an explanation of a natural phenomenon supported by observations and experiments over time

• C. Science undergoes peer review -process by which the procedures and results of experiments are evaluated by scientists in the same field

• D. Science in Everyday Life

– 1. forensics – 2. ethics - A system

defining right and

wrong.

• Here are just a few areas in life science that involve ethics

Human life • abortion

• euthanasia

Heredity - parents and offspring

Animal rights - animal rights vs human rights

Genetics

• - genetic engineering

• manipulating genes

• cloning

• stem cells

Use of the environment - at what financial cost

V. The Methods of Biology

A. Observing and Hypothesizing

• Inferences – process of making logical conclusions

• Scientific methods – used to gather information to answer questions

B. Experimenting

1. Control group and experimental group

2. Independent Variable

3. Dependent Variable

4. Gathering Data– (a) Numerical Data (quantitative)– (b) Verbal Data ( qualitative or descriptive)

5. Analyze Data

C. Conclusion

• 1. Publishing

• 2. Verifying Results

• 3. Revising!!!

D. Tools used in Biology

E. Safety in the Biology Lab