1. 3rd 9weeks Mid-term Study Guide Answers
7th Science
Ely, Hoyman, Jackson

2. What is the process in which a plant or animal species adapts to its environment called?
adaptation
What is the process of passing beneficial traits (traits that help an organism to survive) down to the next generation called?
Natural Selection

3. 3. What are the 4 steps of natural selection?
1) overproduction – producing more offspring than can possibly survive.
2) inherited variation – every individual has its own traits. Similar, but not identical to parents.
3) struggle to survive – some individuals have traits better adapted to environment.
4) successful reproduction - better adaptations are passed down to next generation.

4. What process do plants use to turn the suns energy into food?
Give an example of selective breeding. What makes selective breeding different from natural selection?
Breeding dogs, human breed for the “better traits” that are wanted
What do Geologists study to help them learn what organisms were like in the past?
Fossils
What process do plants use to turn the suns energy into food?
Photosynthesis

5. Describe each of the following: producer, consumer, decomposer
What are the 5 levels of the organization of the environment (in order from least to greatest)?
1. Individual Organism
2. Made of similar organisms; makes a population
3. Made of different populations; makes a community
4. Made of a community and its abiotic environment, which forms an ecosystem
5. All ecosystems, which forms Biosphere
Describe each of the following: producer, consumer, decomposer
Producers: use direct sunlight to make food
Consumers: eat other organisms to get energy
Decomposers: get energy by breaking down dead
What is the difference between a herbivore and a carnivore?
herbivore: only eats plants
carnivore: only eats animals

6. In any food web, what do the arrows represent?
Predators (the item doing the eating)
Put the following in order to correctly show the movement of energy in a food chain. Producer, sun, scavengers and decomposers, consumers.
Sun, producer, consumer, scavengers, decomposers
What is the primary source of energy in all food webs?
SUN
Name two examples of decomposers.
Bacteria, fungi

7. What do the terms biotic factors and abiotic factors mean?
Biotic factors are all living factors
Abiotic factors are the nonliving factors
What are the 3 types of symbiotic relationships?
Mutualism, commensalism, parasitism
Describe a tundra’s environment. (temperature, climate, animals, plants)
Cold temperatures and little rainfall, animals with special adaptations such as polar bear
Describe a desert’s environment. (temperature, climate, animals, plants)
Very hot and dry, plants grow separated from each other, animals are active at night

8. Describe a grassland’s environment
Describe a grassland’s environment. (temperature, climate, animals, plants)
Few trees, has dry seasons, prairie dogs, flowering plants
Describe a rainforest’s environment. (temperature, climate, animals, plants)
Wet, cool, covered by tree canopy, largest diversity in plants and animals
Describe a deciduous forest’s environment. (temperature, climate, animals, plants)
Mild temperature, plenty of rain, trees lose leaves to help conserve water in dry season, much like where we live

9. In a desert ecosystem, would you expect to find more insects or more birds of prey (hawk)? Why?
Insects, heat and water resources
What would happen to the rest of the organisms in an ecosystem if one organism was removed? Explain.
It could change the eating habits, cause some to die out and change the web completely