Basic Biology I Review (Unit 1)
I. Benefits of Studying Biology
A. Learn about one’s surrounding living environment
B. Understand the delicate balance of nature
C. Appreciate the great diversity of species on Earth
D. Learn of food, shelter, and clothing sources in nature
E. Medical advances and disease prevention
F. Protect other life on Earth to sustain the web of life
II. Characteristics of Living Things
A. orderly structure (organization)
B. produce offspring (reproduction)
C. grow and develop
D. adjust to changes in the environment
1.respond
a. physically or mentally
b. maintain homeostasis
2. adapt
3. evolve
III. Environment
A. all the elements making up an organism’s surroundings
1. air/ oxygen, nitrogen, hydrogen, carbon dioxide, argon, etc.
2. water (H2O)
3. soil
a. types
b. minerals
4. temperature
5. weather/ climate
6. light
7. other organisms in the area/ diversity
a. society/ interdependence
b. appearances
c. numbers/ population density
d. gender
e. odors
f. sounds
8. contaminants/ pollution/ chemicals
B. stimuli, i.e. environmental conditions requiring organisms to adjust
IV. Scientific Method
A. Steps
1. Observations
2. Form hypothesis
a. “a testable answer to a question”
b. It is a statement, not a question.
3. Collect data
a. measurements (numerical items)
1. SI units
2. controlled experiments
3. natural phenomenon
b. written observations
c. can support or disprove hypothesis
4. Publish results
a. graphs, charts, tables, plots (Quantitative Research)
b. descriptions of observations (Descriptive Research)
5. Make conclusions/ form a theory
a. Consider references to other similar research
1. Does your work agree or disagree with others?
2. How does your work differ from others’ work?
b.Theories are supported by a large body of evidence.
6. Develop new hypothesis
7. Revise existing theory
a. incorporate new findings
B. Experiments
1. Controls
a. all conditions are kept the same
2. Variables
a. independent variable (I.V.)
1. usually only one I.V. per experiment
2. the condition in the experiment that is changed
3. the factor responsible for the end result
b. dependent variable (D.V.)
1. the condition that results from a change from controls
2. the condition that is measured as the end result
3. Tools
a. devices used to collect, record, and analyze information
b. marked with safety symbols
1. warns of hazards associated with equipment or chemicals
4. Data (Experimental results)
a. numerical
1. measurements of time, size, quantity, temp., etc…
b. verbal
1. words used to describe experimental observations
5. Report Results
V. Atomic Structure
All matter is composed of elements. The smallest unit of matter is the atom. The core of an atom is its nucleus. Inside the nucleus are protons and neutrons. Protons have mass and a positive charge. The atomic number equals the # of protons. Neutrons have no charge but do have significant weight. Elements with the same # of protons but different # of neutrons are isotopes. The atomic weight equals the # of protons + neutrons. Surrounding the nucleus are electrons that orbit the core. Electrons have a negative charge but barely any mass. In an uncharged atom there are equal numbers of electrons and protons. Ions have a different # of electrons than protons. A specific # of electrons occupy each orbital. In the order from closest to the nucleus outward, the maximum # of electrons per orbital for the first 4 energy levels are 2, 8, 18, & 32.
Elements are arranged in order of their atomic number in the Periodic Table. Rows are designated as “periods.” The top row is Period 1, the last is 7. Columns are designated as “groups.” The arrangement of electrons in atomic orbitals accounts for the periodicity of chemical & physical properties of elements.