Cycles

Cycles

Carbon Dioxide

Water

Nitrogen

Carbon Dioxide cycle

Multiple Choice

What causes the heat that we feel on a hot, sunny day?

• decomposers

• the nitrogen cycle

• too much oxygen in the air

• the greenhouse effect

Multiple Choice

Which organisms take in carbon dioxide?

• humans

• trees

• deer

• birds

Multiple Choice

How does carbon get cycled back into the earth?

• through decomposers

• through the greenhouse effect

• through the burning of fossil fuels

• through photosynthesis

Multiple Choice

How does carbon dioxide cycle back and forth between plants and animals?

• plants give off carbon dioxide and animals take in carbon dioxide

• animals breathe out carbon dioxide and plants take in carbon dioxide

• plants and animals both breathe in carbon dioxide

• plants and animals both breathe out carbon dioxide

Multiple Choice

What happens to carbon that has been in the soil for millions of years?

• it ceases to be carbon

• it makes the earth warmer

• it turns into fossil fuels like oil and coal

• it gets cycled back into plants through their roots

Multiple Choice

What happens when gases, like carbon dioxide, get trapped in the atmosphere?

• the temperature of the planet rises

• plants produce more oxygen

• the amount of greenhouse gas decreases

• the number of decomposers increases

Multiple Choice

Which of the following adds to the greenhouse effect and global warming?

• the conservation of national forests

• decreasing the amount of air pollution that is created by cars and buses

• the lessening of carbon emissions into the air

• the burning of too much fossil fuel

Water cycle

Multiple Choice

What is precepitation?

• the sweat from our bodies on hot days

• the gas that we use in furnaces and ovens

• any form of water that falls from the sky

• warm rain nut not cold snow or sleet

Multiple Choice

What is the water cycle?

• the process through which water evaporates

• the path water takes from Earth to the clouds and back again

• the path water takes from the mountain top to the soil

• the process of water falling from the clouds

Multiple Choice

Which of these describes evaporation?

• water vapor becomes a liquid

• plants lose water through their leaves

• what comes down must go up

• water warms up and becomes a vapor

Multiple Choice

What is transpiration?

• the process in which plants release water through their leaves back into the air

• the process in which humans release sweat through their skin back into the air

• what happens when water vapor turns into a liquid

• the scientific name for the water cycle

Multiple Choice

What would most likely happen if it didn't rain in a certain area for a long period of time?

• animals an plants would live the same way they always do

• animals would drink all the water and leave none for the plants

• plants would die and animals wouldn't receive nutrients from plants

• nutrients would find a different way of getting to plants and animals

Multiple Choice

What is the process in which water vapor changes to liquid?

• aviation

• evaporation

• water runoff

• condensation

Multiple Choice

What do water droplets form?

• clouds

• condensation

• nutrients

• humidity

Nitrogen cycle

Multiple Choice

What is the nitrogen cycle?

• the process of chemically producing nitrogen to be used by plants and animals

• the process of continually recycling nitrogen from living things to non-living things between Earth and its atmosphere

• the process green plants use to make food

• the process of recycling carbon from living things to non-living things between Earth and its atmosphere

Multiple Choice

How do humans get nitrogen?

• by breathing it in

• by drinking water

• by eating plants

• by producing it naturally in their digestive system

Multiple Choice

Which of the following comes first in the process of nitrification?

• plants use nitrates to create protein

• bacteria in the plant turn the nitrogen gas into ammonia

• bacteria turn the nitrites into nitrates

• nitrogen gas travels from the air to the soil

Multiple Choice

How do nitrates turn back into nitrogen gas?

• animals release nitrogen gas when they breathe out during respiration

• plants give off nitrogen gas after they have used all the nitrates that they needed

• plants and animals die and decomposers release nitrogen gas back into the air

• bacteria turns the nitrates back into nitrogen gas which gets released through the roots of the plant and back into the air

Multiple Choice

Which of the following is one of the key components of the nitrogen cycle?

• carnivores

• rain

• the sun

• bacteria

Multiple Choice

What do plants and animals use nitrates for?

• to produce sugars they need for energy

• to create the protein they need to live ans grow

• to aid in photosynthesis and respiration

• to assist in digestion

Multiple Choice

How are people upsetting the nitrogen cycle?

• by building up too much nitrogen in the air

• by creating too much bacteria in the soil

• by riding their bikes

• by breathing in too much nitrogen

Multiple Choice

Which of the following is one of the key components of the nitrogen cycle?

• carnivores

• rain

• the sun

• bacteria