Name: _________________________________________________
Date: ___________
Ch. 3, Ecosystems
Study Guide
o In a desert environment, you might see adaptations such as plant stems expanding
and filling up with water after rainfall.
o A population is all the members of one species that live in part of an ecosystem.
o The energy that flows in ecosystems originally comes from sunlight.
o A producer is different from a herbivore because producers make their own food, but
herbivores get energy by eating producers.
o The best explanation for a decrease in a population of birds in a community is that the
amount of food decreases.
o An organism that gets its energy by eating dead plants and animals is a scavenger, or
a decomposer.
o Decaying organisms in a swamp help create the next generation of
organisms because they put minerals and nutrients back into the soil.
o Zooplankton is an animal, and is therefore a consumer in a food web.
o Scavengers and decomposers help ecosystems because they return minerals and
nutrients to the ecosystem.
o Because wolves hunt in a pack, they can compete successfully for food.
o Two examples of the living parts of a forest ecosystem are deer and trees. Two
examples of the nonliving parts of a forest ecosystem are sunlight and soil.
o The adaptation that would be most useful to an animal whose niche is eating nectar
from plants would be wings.
o Sunlight is the main energy source for life on Earth.
o Plants are producers, so grass is a producer.
o The desert ecosystem has living things that have adapted to survive in the most limited
water supply.
o The adaptations that are MOST LIKELY found in animals that are carnivores are claws
and sharp teeth.
o Plants are producers and they change energy from sunlight into chemical energy.
o A food web is a group of overlapping food chains.
o Green plants change sunlight into a usable energy source by making food through
photosynthesis.
o A decomposer is an organism like an insect that eats the wastes or remains of dead
plants or animals.
o A community is the different populations that interact in an area of an ecosystem.
o Organisms living in a tundra ecosystem need to adaptations to a cold, dry climate
where the ground is frozen year-round to survive.
o If most of a population of animals dies of disease, the food web must change.
o An omnivore is an animal that eats plants and animals.
o Nutrients and minerals (energy) that animals need travel through a food chain.
o A prairie dog’s burrow is its habitat.
o A food chain shows the direction of energy flow in an ecosystem.
o A food chain is different from a food web because in food webs, there are several
overlapping food chains.
o The difference between herbivores and omnivores is that both get energy by eating
plants, but omnivores also eat animals.
o An ecosystem is best described as a system where living and nonliving things interact.
o The most important reason to store food in a refrigerator is because food decays more
slowly in colder temperatures.
*** BE SURE TO STUDY THE DEFINITIONS OF THE VOCABULARY TERMS FOR CHAPTER 3:
 ecosystem
 niche
 herbivore
 decomposer
 population
 omnivore
 community
 carnivore