Unit 1 Lesson 3

Question 1

All organisms need _____ to perform their functions throughout their lives

Answer 1

energy

Question 2

_____ are a complex organization of interdependent parts

Answer 2

ecosystems

Question 3

A _____ is a pathway that energy and nutrients can follow through an ecosystem

Answer 3

food chain

Question 4

_____ make up the first level of a food chain

Answer 4

Producers

Question 5

Insects and other plant eaters get energy by eating _____

Answer 5

producers

Question 6

_____ complete the food chain

Answer 6

Decomposers

Question 7

Decomposers break down _____ and _____, where they can be used by producers

Answer 7

nonliving plant and animal matter; return nutrients to the soil

Question 8

The interconnected food chains are called _____

Answer 8

food webs

Question 9

a representation of the energy available at each level of a food web.

Answer 9

Energy Pyramid

Question 10

When an organism obtains energy, most of the energy is used for _____

Answer 10

life processes

Question 11

The _____ level—the _____ —has the most energy

Answer 11

bottom; producers

Question 12

Consumers at the highest level have the _____ amount of available energy

Answer 12

least

Question 13

As one organism eats another organism in a food web, both _____ are transferred to the body of the consumer

Answer 13

energy and matter

Question 14

Wherever water moves, _____ is at work

Answer 14

energy

Question 15

_____, ______, and _____ are processes that cycle carbon

Answer 15

Photosynthesis; cellular respiration; the digestion of food

Question 16

All energy food sources are made of _____ that are needed for growth and life

Answer 16

carbon-based molecules

Question 17

Decomposition returns _____ stored in the remains of organisms to the environment

Answer 17

carbon

Question 18

_____ speeds up the transfer of carbon from the earth to the air

Answer 18

Burning fossil fuels

Question 19

_____ slows down the transfer of carbon from the air to living things

Answer 19

Cutting down forests

Question 20

Cells use _____ to build many life molecules

Answer 20

nitrogen

Question 21

Nitrogen enters most food webs when _____ or _____ take up these forms of nitrogen

Answer 21

plants; algae

Question 22

Decomposers return _____ to the soil and water, where bacteria can change it back to a gas form, returning it to the air

Answer 22

nitrogen