1. The Science of life
Chapter 1
Biology II

2. Vocabulary- The Science of Life- 22 words
Biology development Organization reproduction Cell gene Unicellular domain Multicellular kingdom Organ ecology Tissue ecosystem Organelle evolution Biological molecule natural selection Homeostasis adaptation Metabolism Cell division

3. A. The World of Biology
Biology: the study of life
Biologists study many different kinds of life from very tiny to very large
Biologists investigate subjects that affect you and the way you live

4. 4. Characteristics of Life
All living things share seven characteristics
1. Organization and Cells
a. Organization: the high degree of order within an organism’s internal and external parts and in its interactions with the living world

6. b. Cell: the smallest unit that can perform all life’s processes
1. unicellular: made up of one cell
2. multicellular: made up of multiple cells
Organs: structures that carry out specialized jobs within an organ system
Tissues: groups of cells that have similar abilities and that allow the organ to function
Organelles: within each cell, tiny structures that carry out functions necessary for the cell to stay alive
Biological molecules: the chemical compounds that provide physical structure and function

7. 2. Response to Stimuli- must be able to respond and react to changes to stay alive
Homeostasis- the maintenance of a stable level of internal conditions even though environmental conditions are constantly changing
Metabolism- the sum of all the chemical reactions that take in and transform energy and materials from the environment

8. 5. Growth and Development
Cell division: the formation of two new cells from an existing cell
Development: the process by which an organism becomes a mature adult

9. Reproduction: the production of new organisms
Essential for the continuation of a species
Gene: a short segment of DNA that contains the instructions for a single trait of an organism
Sexual reproduction(resulting offspring not identical to parents)/asexual reproduction (resulting offspring identical to original)
6. Reproduction

10. 7. Change through time- populations of living organisms evolve or change through time

11. B. Themes in Biology
Diversity and Unity of Life
a. All living things share certain sets of genes, inherited from a single common ancestor
b. Different species possess certain sets of genes unique to them

12. c. Three domains of life
domain: major subdivisions of all organisms
Bacteria, Archea, and Eukarya
Domains are divided into the following six kingdoms:
a. Domain Bacteria- Kingdom Bacteria
b. Domain Archaea- Kingdom Archaea
c. Domain Eukarya- Kingdoms Protista, Fungi, Plantae, and Animalia

13. 2. Interdependence of Organisms
Ecology: the branch of biology that studies organisms interacting with each other and with the environment
Ecosystems: communities of living species and their physical environment
all organisms are interdependent upon one another and their environment for survival

14. 3. Evolution of Life
Evolution (descent with modification): the process in which the inherited characteristics within populations change over generations, with giving rise to new species
Evolution helps construct the “tree of life”
Natural selection: organisms with certain favorable traits are better able to survive and reproduce successfully than organisms that lack these traits

15. d. Adaptations: traits that improve an individual’s ability to survive and reproduce