What is Biology?

Biology is the Study of Life Biologist study the

interactions of life. Entomologist Anthropologist Ornithologist Etc…

How does science define life? There are 8 different Characteristics that an

organism must have to be considered. What might these be?

Cells/Organization Living things are highly

organized: they are all composed of tiny living units called cells.

Cells are the smallest units that are considered alive.

Some organisms consist of only a single cell, others have trillions. Multicellular Unicellular

Image from: http://www.time.com/time/daily/special/genetics/ethics.html

Obtain and use energy

Living things take in energy to grow, develop and reproduce.

The chemical reactions that build up or break down materials is called metabolism.

Image from http://photographytips.com/page.cfm/3575

Reproduction Individual organisms

die, but the species continues because of reproduction.

Reproduction without genetic contribution from two parents is called asexual.

Sexual reproduction produces offspring with genetic material from both parents.

Imae from http://www.karlloren.com/biopsy/p66.htm

Image from http://www.cccturtle.org/contents.htm

Growth and Development Living things grow over

their lifetimes. Single- celled

organisms increase their volume and multicellular organisms add to the number of cells in their body.

Development example:

seed to apple treeImage from http://www.sosun.com/company.html

Response to the Environment When presented with

the proper stimulus, a living organism will respond.

Example: chemical produced by a plant to keep caterpillars away.

Image from http://greennature.com/gallery/caterpillar-pictures/cinnebar-caterpillar.html

Living things evolve Groups of organisms

will evolve or change over time.

Evidence of these changes can be found in living things and fossils.

Ex: Cooksonia (moss like)

satorismiles.com/.../

Maintain stable internal environment

Organism must keep their internal environment stable even when the external environment changes.

Maintaining an organisms internal environment is referred to as homeostasis.

Ex: humans internal temperature

Universal genetic code All information needed to live and grow is

stored in a genetic code known as DNA. Information is passed from parent to

offspring.http://www.ucmp.berkeley.edu/glossary/gloss3/DNA2.gif

Any Questions?Let’s review….What are the characteristics of life?