The Study of Life Biology is the scientific study of living organisms
Characteristics of Life Properties that all organisms share
8 Characteristics of Life 1. made of cells 2. reproduce 3. universal genetic code (DNA) 4. grow and develop 5. take in energy (food) 6. respond to environment 7. maintain internal environment 8. undergo life processes
Cells Smallest unit of life Unicellular: one cell – Bacteria Multicellular: many cells humans, animals, plants
Reproduction Producing new organisms Asexual: one parent Sexual: two parents
Universal genetic code Directions for what traits an offspring will have Carried on DNA
Grow and Develop Growth: becoming larger Development: changes during a lifetime Lifespan: period of time an organism lives Life Cycle: all the changes organisms go through during its life span
Do organisms always grow and develop at the same rate? When do organisms stop growing and developing? THINK!!
Matter and Energy Eating gives materials for growth, development, reproduction Energy comes from chemical reactions from food
Response to Environment All living things live in constantly changing environments Must change in order to survive Stimulus: what cause change to occur touch, light/dark, etc. Response: reaction to a change in environment
Response to stimuli and adjust to surroundings
What happens to the eye?
Maintain stable internal environment Organisms keep things internally pretty constant Homeostasis: process of keeping internal conditions relatively stable
As a group, living things change over time Evolution: changes that take place over millions of years Individual does not change
Life Processes Provides what is needed to survive Ingestion: taking food into the body Digestion: process of breaking down food
Life processes Photosynthesis: food-making process; plants Chemosynthesis: chemical energy to make food
Life Processes Cellular Respiration – using food to produce energy
Life Processes Excretion: removal of waste products Transport: moving nutrients throughout an organism