Transcript Studying Life - Southgate Schools

Studying Life
1-3
Biology
• Means study of life
• Science that seeks to understand the
living world
• In order to be considered alive,
organisms must meet 8 criteria
1. Made up of cells
• Cells - smallest unit of life
• Unicellular - made of 1 cell
• Multicellular - made of several cells
2. Reproduction
• Produce new organisms through a
process called reproduction
• Asexual - single parent, divides in 2,
creates identical offspring
• Sexual - 2 parents, genetically different
offspring
3. Based on a Genetic Code
• Offspring inherit traits from parents
• Directions for inheritance carried in DNA
- genetic code
4. Growth and Development
• All living things grow during at least part
of their lives
• Some, like bacteria, just grow in size
• Multicellular organisms go through
stages of development
5. Need for Material & Energy
• Organisms need materials and energy
to grow, develop, and reproduce
• Get energy from photosynthesis or
consuming energy stored from
photosynthesis
• Metabolism
6. Response to Environment
• Organisms detect and respond to
stimuli from environment
• External stimuli - light & temp.
• Internal stimuli - blood sugar level
7. Maintaining Internal Balance
• Organisms must keep internal temp.
and water content fairly constant to
survive
• Homeostasis - maintaining internal
balance
– Shiver, sweat
8. Evolution
• As a group, organisms evolve, or
change over time
• Ex. - fish bony plates to scales
Levels of Organization
Biosphere
Ecosystem
Community
Population
Organism
Groups of cells
Cells
Molecules