Name ________ANSWER
KEY
Period _________
Study Guide: Ecosystems
Directions: Read pg. 558-565 and pg. 586-588 in Science Explorer and answer the
following questions.
Components of an Ecosystem
1. What is an ecosystem?
All the living and nonliving things that interact in a particular area
2. What is the difference between biotic and abiotic factors?
Biotic factors are the living parts of an ecosystem.
Abiotic factors are the nonliving parts of ecosystem.
3. Study Figure 2 on pg. 559. What are some abiotic factors in this ecosystem?
Rocks, sand, dirt, air, sunlight
4. Study the picture on pg. 238-239 in your textbook. Does the illustration represent an
ecosystem? Why or why not?
This is an illustration of an ecosystem because it contains both biotic and abiotic factors
in a given area.
5. An organism is an individual living thing. A ___species_______ is a group of similar
organisms that can mate with one another and produce fertile offspring.
6. What is the habitat of an organism?
the place where an organism lives and that provides the things an organism needs
7. What is the niche of an organism in an ecosystem?
the role an organism has in the atmosphere
8. Describe the habitat and the niche of the desert cottontail rabbit in a desert ecosystem.
The rabbit lives in areas of brush in deserts and grasslands. The niche of this rabbit
includes:
1. type of food it eats
leaves, grasses, seed pods
2. what eats the rabbit
hawks, owls
3. behavior
noctrunal
Energy Flow in an Ecosystem
9. Complete the chart that names and describes the three energy roles of organisms in an
ecosystem.
Energy Role
Function
Examples
Producers
Source of all food energy in
an ecosystem
Plants, algae, plankton
Consumers
Obtains energy by feeding
on other organisms
Caterpillars, humans,
snakes, lions, vultures
Decomposers
Break down wastes and dead Bacteria,
organisms and return
Fungi (molds, mushrooms)
nutrients to the soil
10. Complete the compare/contrast table that describes the different types of consumers.
Type of Consumer
Herbivore
Type of Food
Eats only plants
Carnivore
Eats only animals
Omnivore
Eats both plants and animals
Scavenger
Feeds on the bodies of dead organisms
11. Energy is described as the capacity to do work. All organisms need energy to survive.
What is the ultimate source of energy in an ecosystem? the sun
12. Food chains and food webs show how _____energy__________ is transferred through
an ecosystem.
13. What is a food chain? A series of events in which one organism eats another and
obtains energy. A food chain shows the path of energy through an ecosystem.
14. Label the producer and the first and second level consumers in the food chain below.
Grass
Rabbit
Producer
First Consumer
Eagle
Secondary Consumer
15. The many overlapping food chains in an ecosystem form a ___food web__________.
16. An energy pyramid shows the __amount____ of energy passed from one feeding level
to another in a food web.
17. Each level of the pyramid uses the majority of its __energy_____ to stay alive. Only
__10 _ % of the energy in one level of the pyramid is transferred to the next, higher
level.
Use the energy pyramid below to answer the following questions.
A
B
C
D
18. Which level represents a plant eater? ______C_________
19. Which level has the most food energy available? ______D_______
20. Which level receives energy directly from the sun? ______D________
21. What would happen to the size of Level B if Level C decreased in size? Why?
Level B would decrease in size because its main source of food energy (Level C) has
decreased.