Chapter 1: The Science of Life
Section 1: The World of Biology
I. Biology and You
A.) Biology: The study of life; offers an organized and scientific framework for
asking and answering questions about the natural world.
1.) Ask different types of questions
a.) How do living things work?
b.) How do living things interact with the environment?
c.) How do living things evolve?
2.) Study different types of living things
a.) Unicellular organisms (bacteria)
b.) Multicellular organisms (animals, plants, fungi)
c.) Viruses
B.) Biology and Society
1.) Helps you make informed, ethical decisions
2.) Learn about new tools and technology
3.) Understand how the environment is changing
II. Characteristics of Life
A.) Organization and Cells: Order within an organism, whether it is unicellular
(bacteria) or multicellular (animals, plants)
1.) Multicellular organisms display the following organization: cells
(smallest unit of life that can carry out all of life’s processes), tissues
(groups of cells with similar functions), organs (tissues with specialized
jobs), organ systems (all the organs of a particular body system that
work together)
Cells Tissues Organs Organ Systems
2.) Organelles: Only in eukaryotic cells; different structures within a cell
that have different jobs
3.) Organelles contain biological molecules (DNA, proteins, lipids/fats,
carbohydrates)
B.) Response to Stimuli
1.) Reacting to a change in the environment
2.) Give an example (provided by book or, better, one you think of on
your own)
C.) Homeostasis
1.) Maintenance of a stable internal environment
2.) Give an example (temperature, water content, blood pH)
D.) Metabolism
1.) Sum of all the chemical reactions that take in and transform energy
and materials from the environment
2.) Plants = photosynthesis, animals = cellular respiration
3.) Necessary for repair, growth, and movement
E.) Growth and Development
1.) Caused by both an increase in the number of cells and cell
enlargement
2.) Cell Division: Forming two new cells from one cell; unicellular
organisms must first enlarge before they divide
3.) Development: Changes that occur during growth as an organism
advances through its life stages
a.) Cell division
b.) Cell differentiation/specialization
F.) Reproduction
1.) Production of offspring
2.) Not required for that organism’s survival, but required for survival of
thespecies
3.) Necessary for passing down DNA, which contains genes: regions that
code for traits
a.) Sexual Reproduction (two organisms each contribute genetic
information)
b.) Asexual Reproduction (one organism, such that offspring is
identical
G.) Change Through Time(Evolution)
1.) Individuals don’t evolve; populations evolve
2.) Must adapt to changing environment in order to survive