1. Characteristics of Life

2. What is Biology? Biology is the study of living things
Some branches of biology include biochecmistry ecology, cell biology, genetics, evolutionary theory, microbiology botany, zoology, and physiology
What is a living things? All living things share several properties.

3. 1.Cellular Organization
All living things are made up of cells
Cell-the smallest unit of living matter that is enclosed by cell membrane that separates it from its surroundings
Unicellular- describes living things made up of only 1 cell
Multicellular-describes living things made up of many cells

4. 2. Homeostasis All living things maintain an internal balance
Homeostasis-process by which organisms keep their internal conditions relatively stable.
An organism’s homeostasis is threatened by changes in its environment
Examples of how organisms maintain homeostasis:
Sweating
Shivering
Physical movement

5. 3. Metabolism
Living things carry out many chemical reactions in order to obtain energy
Organisms need materials and energy to grow, develop, reproduce, and stay alive.
Metabolism-the combination of chemical reactions in which an organism builds up or breaks down materials as it carries out its life processes.

6. 4. Responsiveness Living things respond to their environment
Stimulus- any change in an organism’s environment
Response- an organism’s reaction to a particular stimulus
Examples:
Flower bends toward light
Bird fluffs feathers when cold

7. 5. Reproduction
Process by which organisms make more of their own kind from one generation to the next
Sexual Reproduction- two cells from different parents unite to produce a new organism.
Asexual Reproduction- a single parent reproduces to form a new organism

8. 6. Heredity
Process of organism passing on its own traits to its offspring
Life is based on a universal genetic code- the genetic code of DNA determines the inherited traits of every living organism on Earth (with only minor exceptions.)

9. 7. Grow and Develop Growth- an increase in cell size and number
Development- a change that occurs in an organism
Examples:
Caterpillar
Tadpole

10. Evolution Evolution-change over time
When a new species develops from preexisting species over time.
A group of living things can evolve or change over time
The ability of a group to change over time is invaluable for survival in a world that is always changing.