INTRODUCTION TO BIOLOGY
I. DEFINITION
A. BIOLOGY
1. bio1. Life
1. -ology
2. Scientific study of
II. CHARACTERISTICS OF LIFE
A. Order
1. Molecules
a. Biochemists and molecular biologist often study this level of biological
organization
2. Organelles
3. Cells
a. Cells are the smallest unit of life
b. Cytologists study cell structures
4. Tissues
a. Group of like cells that come together to perform a function
b. Histologists study tissues
5. Organs
a. Two or more tissues that come together to perform a function
6. Organ systems
a. Two or more organs that work together to perform a function
7. Organisms
a. Organismal biologist study organisms
b. Usually specialized
1. Bacteriologist study bacteria, botanist study plants, zoologist
study animals, etc.
8. Populations
a. Members of a species in a certain area
9. Communities
a. All members of all species in a certain area
10. Ecosystems
a. All members of all species in a certain area interacting with each other
and abiotic factors
B. Reproduction
1. Sexual
a. Two genetically different organisms donate genetic information to form
an offspring that is genetically different from both parents
2. Asexual
a. One parent donates all the genetic information to the offspring
b. Offspring are identical to each other and to the parent
C. Growth and development
D. Performs work / Utilizes energy
1. Energy
a. Ability to do work
b. Sources
1. Chemotrophs
a. Uses chemical energy
2. Phototrophs
a. Use light energy
2. Types of work
a. Transport
b. Chemical
c. Mechanical
E. Responds to stimuli
F. Homeostasis
1. Most organ systems function to keep the body's internal environment
approximately constant
G. Adaptation
1. Organisms with genetic modification that make them most suitable for their
habitat will have more offspring than organisms less well adapted to their
habitat
2. Over time, more and more members of the species will inherit these
adaptations and the species evolves