The Flow of Matter and Energy Unit Review
Ecology
1. List and define the three symbiotic relationships.
Parasitism – one organism lives in or on another organism and harms it
Mutualism – both organisms benefit
Commensalism – one organism benefits and the other is unaffected
2. How do energy and matter flow through food chains and food webs? (autotrophs, heterotrophs, consumers, herbivores,
omnivores, carnivores, trophic levels, etc.)
Energy flows from the sun to producers (photosynthesis) to consumers
3. Draw a five trophic level food chain. Label each trophic level. Label each organism as an autotroph or heterotroph.
Producer (autotroph) Primary ConsumerSecondary ConsumerTertiary ConsumerDecomposer
4. If 2500kCal of energy is available at the 3rd trophic level, how much is available at the first trophic level?
250,000kCal
5. What type of trends (population, biomass, energy) are reflected in ecological pyramids?
Population, biomass, and energy decrease as you go from producer to consumer
6. How does the change in the size of a population in a food chain affect the size of other populations in the food chain?
Decreasing the population of an organism would cause the trophic level after it to decrease (less food) and before it to increase
(less predators)
7. In what ways does matter (water, nitrogen, phosphorus, carbon) cycle through ecosystems and how are organisms involved in the
cycling?
Carbon and water are cycled through photosynthesis, respiration, producers, consumers, and decomposition
Nitrogen is cycled through nitrogen fixation (bacteria), producers, consumers, and decomposition
Phosphorus is not in the atmosphere – it is only cycled through producers, consumers, and decomposition
8. What are all organisms dependent on other organisms (biotic factors) as well as their environment (abiotic factors)? Give specific
examples of interdependence.
Organisms affect each other through relationships such as predator/prey, symbiosis, and competition. The abiotic factors of an
ecosystem (temperature, precipitation, soil type) will affect what plants and animals can live there.
9. What is meant by energy transformation (conversions)? Name forms of energy and give examples of energy transformations.
Omit
10. How do the climatic conditions determine the biodiversity in an area?
Plants and animals are adapted to the climate of an area. For example, very few plants and animals can survive in deserts and
tundras due to the harsh temperatures and low precipitation.
11. Compare and contrast the tropical rainforest with the desert. Discuss the environmental factors that affect photosynthesis and the
relationship this has on the diversity of the region.
The TRF has high temperatures and precipitation which allows for a large amount of plant life. Therefore, consumers have plenty
of resources and the TRF has the highest amount of biodiversity. Few plants can survive the dryness of the desert, so there are
fewer consumers due to limited resources.
12. How are the movement of matter and the movement of energy through an ecosystem different?
Matter is cycled, energy flows or is passed from one for to another
Photosynthesis
13. What are the reactants of photosynthesis and explain where producers get each of them.
carbon dioxide (stomata), water (roots)
14. What are the products of photosynthesis? What happens to each of them when they are produced by autotrophs?
oxygen (released from the stomata) and glucose (stored in the cell for respiration)
15. What organelle is responsible for photosynthesis?
chloroplast
16. What type of energy conversion occurs during photosynthesis?
Light energy is converted to high-energy sugars (glucose)
17. Discuss the relationship between wavelength, frequency, and color.
Omit
18. Chlorophyll is a green pigment found in almost all autotrophs. What is the role of chlorophyll in photosynthesis?
Absorbs light
19. How do environmental conditions affect the rate of photosynthesis?
Plants need water, sunlight, and moderate to high temperatures
20. What are stomata? What structure regulates the opening and closing of stomata?
Openings on the underside of the leaf that allow gas exchange; guard cells
Cellular Respiration
21. What changes in matter and energy occur during the respiration reaction? Where in the cell does respiration occur?
Glucose and oxygen are used to produce water, carbon dioxide, and ATP
22. Draw and animal cell. Show the reactants of respiration; explain where they come from and where they end up in the cell. Show
the products of respiration and what happens to them after they are made by the cell.
Reactants – oxygen (breathing) and glucose (eating or stored in the cell)
Products – water and carbon dioxide (byproducts) and ATP (used for cell work)
23. What is the goal of cellular respiration?
Break down glucose to produce ATP for cell work
24. What is oxygen’s role in cellular respiration? Compare and contrast aerobic and anaerobic respiration.
Used to break down glucose; anaerobic does not use oxygen but produces less ATP
25. What is the ONLY energy source that can directly power cells?
ATP
26. Describe at least three types of cell work.
Cell growth, active transport, making proteins, cellular division, moving organelles, performing photosynthesis, etc.
27. Explain the recycling of matter in the ATP cycle and the associated flow of energy.
The energy from the bonds of glucose is used to add a phosphate group to ADP to form the ATP molecule (36 ATP are made
from 1 glucose in aerobic cellular respiration). The ATP is used for cell work, but to release the energy for cell work the third
phosphate group must be removed. Breaking that bond releases the energy.
28. How do respiration and photosynthesis represent the cycling of matter?
The reactants of photosynthesis are the products of cellular respiration and vice versa
29. Draw the energy flow diagram. Summarize the flow of matter and energy.
See your notes