Studying Life Section 1-3 Identify characteristics of living things. Explain how life can be studied at different levels.

Brainstorm Characteristics of Living Things Made up of cells Reproduce Grow and develop Obtain and use materials and energy Respond to stimuli (or environment) Maintain a stable internal environment (homeostasis) As a group, change over time (evolve) Based on a universal genetic code

1. Made Up of Cells Describe a cell. Def: Living matter enclosed in a barrier that separates it from its surroundings The smallest units of an organism that can be considered to be alive! What characteristics of life do cells exhibit?

2. Reproduction 2 types: Which type do you think is most common? Sexual reproduction – cells from 2 different parents unite to form the first cell of a new organism (example?) Asexual (“a” = “not”) – single parent (example?) Which type do you think is most common?

3. Grow and Develop Define “growth”. What is the difference between “growth” and “development”? Do all organisms exhibit BOTH? Can nonliving things exhibit growth and development? You are actually at one of the biggest development stages in your life. When does growth and development stop?

4. Obtain and Use Materials and Energy What is the purpose of this? It is like building a house with materials gathered and energy used. (And there are always waste products left over!) Organisms gather materials, break them down and make new materials through chemical processes. The combination of all these processes is called metabolism. So where do we get these materials and energy?

5. Respond to Stimuli (or Environment) Stimulus: a signal to which an organism responds (examples?)

6. Maintain a Stable Internal Environment (Homeostasis) Examples: temperature, respiratory rate

7. As a Group, Change Over Time (Evolve) What do we mean when someone says you’ve adapted to your new situation (i.e., city, school, teacher, break-up)? How can a plant become adapted to changing environmental conditions? In biological terms, “adaptation” is a long-term process of change. Individuals don’t adapt; a group of organisms changes over time. How does this type of adaptation occur?

8. Based on a Universal Genetic Code Back to reproduction – organisms inherit DNA from their parent(s), which can cause different traits to be passed along. “Only the strong survive” 

Branches of Biology 2 main categories: Theoretical science Build on the science knowledge base Examples: microbiologists, botanists, paleontologists, ecologists Applied or Practical science USE the knowledge of theoretical science to improve life Examples: physicians, medical researchers, wildlife managers, foresters

Levels of Organization Molecular – groups of atoms (water, DNA, proteins, etc) Cells – plant, nerve, bacteria Groups of cells – tissues, organs Organism – individual living thing Population – group of organisms of ONE TYPE that live in the same area Community – all populations that live together in the same area Ecosystem – a community and its nonliving surroundings Biosphere – the part of Earth that contains all ecosystems