Ecosystems & Energy
What is a producer?
An autotroph that makes its own food.
What is a niche?
The role of an organism in its environment.
What organelle performs photosynthesis?
Chloroplast.
What does the nucleus do?
Holds DNA and controls the cell.
What is diffusion?
Movement from high to low concentration.
What is the Rule of 10?
Only 10% of energy/biomass moves to the next trophic level.
What is competition?
Organisms fighting for the same resources.
What is ATP?
A molecule that stores and releases energy for cells.
What organelle packages materials for transport?
Golgi apparatus.
What is osmosis?
Diffusion of water across a membrane.
What is the difference between a food chain and a food web?
Food chains are simple feeding paths; food webs show many interconnected feeding relationships.
What is the difference between mutualism and parasitism?
Mutualism benefits both species; parasitism benefits one and harms the other.
Compare photosynthesis and cellular respiration.
Photosynthesis stores energy in sugar; respiration releases energy from sugar.
Name 3 structures found in plant cells but not animal cells.
Cell wall, chloroplast, large central vacuole.
Compare passive and active transport.
Passive transport needs no ATP and moves high → low; active transport requires ATP and moves low → high.
Explain why energy is said to “flow” through an ecosystem.
Energy enters from the sun and leaves as heat, so it flows one direction.
What is carrying capacity?
The largest population an ecosystem can support.
Why do plants need both chloroplasts and mitochondria?
Chloroplasts make sugar; mitochondria break sugar down for ATP.
Compare prokaryotes and eukaryotes.
Prokaryotes lack a nucleus and membrane-bound organelles; eukaryotes have them.
Explain what happens to animal and plant cells in hypertonic and hypotonic solutions.
Hypertonic = cells shrink; hypotonic = animal cells may burst and plant cells become turgid.
Describe the carbon cycle and how humans impact it.
Producers absorb CO2, organisms release CO2 through respiration, decomposition and burning fossil fuels release stored carbon.
Explain primary vs. secondary succession and identify a climax community.
Primary succession begins on bare rock; secondary begins where soil remains. A climax community is the stable final stage.
Explain aerobic vs. anaerobic respiration and ATP production.
Aerobic respiration uses oxygen and makes 38 ATP; anaerobic does not use oxygen and makes 2 ATP.
Explain the Cell Theory.
All living things have cells, cells are the basic unit of life, and cells come from preexisting cells.
Compare endocytosis, exocytosis, phagocytosis, and pinocytosis.
Endocytosis brings materials in, exocytosis sends materials out, phagocytosis takes in solids, pinocytosis takes in liquids.