1. The Science of Biology

2. What is Biology? Biology: The study of Life!! But…
What exactly do we mean by “Life” ?

3. The 8 Characteristics of Life…

4. CELLS Unicellular Multicellular All life is made up of cells
A cell is the smallest unit
that is still considered alive!
Unicellular: one cell
Multicellular: many cells
Unicellular
Multicellular

5. All life can make new life!
Reproduction
All life can make new life!
Asexual=cloning, budding, regeneration
Sexual=Sperm and Egg

6. Based on a UNIVERSAL Genetic Code
-Genetic info stored in a molecule called DNA

7. Growth & Development All organisms grow and Develop
Growth: increase in size
Development: cells increase in number and become different (differentiate)

8. Need Materials for Energy
All living things use energy:
Energy is obtained by breaking down complex “food” molecules
Photosynthesis: using light energy to make “food” (sugar).
This is the only way energy enters terrestrial food webs
Consumption: Must “steal” energy from others
Metabolism: combination of chemical reactions through which all organisms build up or break down materials
Consumption
All living things HAVE METABOLISM!
Photosynthesis

9. Response to the Environment
Examples:
A plant seed only germinates when there is sufficient water and temperature.
Plant roots grow down.
Plant leaves grow towards sunlight.
Watch this
Stimuli
Heat
Light
Pressure
Sound
Gravity

10. Maintaining Internal Balance
Homeostasis: process by which organisms keep their internal conditions relatively stable
Example: How do humans maintain the same body temperature?
Sweat
Shiver

11. EVOLUTION To Evolve: To change over time
A group of organism can change over many generations
leg bone in a whale

12. The Many Branches of Biology
Diversity of life is so great, biology is separated into branches
Zoologists: study animals
Microbiologists: study bacteria
Botanists: study plants
Ethologists: study animal behavior
Paleontologists: study life from the past
Biotechnology is the application and use of knowledge acquired through these and other branches