Ecology Chapter 20Cycles of Matter

Lesson #2

Science 7Guided Note Set

Mr. Nigh

PretestPut your name and hour on a lined

sheet of paper

Answer the following questions individually to the best of your ability

The data from this exercise will only be used to provide a direction for future discussions

1. The scientific study of how organisms interact with their environment.

A. Biology

B. Chemistry

C. Ecology

D. Astrology

2. What is the primary source of energy for most ecosystems?

A. Water

B. Nitrogen

C. Oxygen

D. Sunlight

3. Which organism is a decomposer?

A. Vulture

B. Sunflower

C. Musk Ox

D. fungi

4. Which factor is least important in determining the plant life in a biome?

A. Average rainfall

B. Average temperature

C. Type of soil

D. Type of animals living there

5. Which is not an abiotic factor?

A. plants

B. sunlight

C. water

D. temperature

6. Which is not a producer?

A. Seaweed

B. Corn

C. Caterpillar

D. Trees

7. Which of the following is a consumer?

A. Mushroom

B. Grass

C. Plankton

D. bird

8. Which is not a biotic factor?

A. Leaves

B. Water

C. Trees

D. snakes

9. Large geographic areas that are characterized by a certain climate, plants, and animals.

A. Ecosystems

B. Estuaries

C. Biomes

D. Countries

10.Trees that grow their leaves in the spring and drop them in the fall are known as?

A. Coniferous

B. Taiga

C. Evergreen

D. Deciduous

Background Information

1. All organisms must take in water and food to survive

2. All of the materials an organism takes in are returned to the ecosystem.

3. This process takes place while the organism live and after it dies

Cycles

1. The movement of matter through the living and non-living parts of an Ecosystem.

2. It is a continual process3. The three most important

cycles in ecosystems involve water, carbon, and nitrogen.

Quick Quiz

What are the three most important cycles in

ecosystems?

Water

Carbon

Nitrogen

The Water Cycle1. Water is stored on Earth’s surface in

rivers, lakes, and oceans.

2. Water is found underground

3. Large amounts of water is stored in polar regions in glaciers and polar ice sheets.

4. The movement of water through the environment is the Water Cycle.

5. Water is made up of two elements-hydrogen and oxygen

6. It changes its state of matter between three forms in the water cycle

A. gas

B. liquid

C. solid

Gasses

• Water returns to the atmosphere when heated, changing back into a vapor, a process known as evaporation

• Animals release water vapor when they breathe through respiration

• Plants release water vapor through transpiration

Quick Quiz!What are the three ways that water

is returned to the atmosphere by heat, plants, and animals

Evaporation by heat

Transpiration by plant

Respiration by animals

Liquids and Solids

Water that falls to the Earth’s surface is referred to as precipitation

Could fall as rain, mist, sleet, hail, or snow

If the temperature is cold enough, precipitation is stored as ice

Evaporation• Evaporation is the process during which

liquid water changes into a gas called water vapor

TranspirationCover ½ of plant with a plastic bag

Put into a warm environment

Water thoroughly

Watch for water vapor to occuron the inside of plastic bag as water vapor escapes from leaves

About 10% of water vapor in the atmosphere comes from transpiration or water passing from plants to the atmosphere

Condensation

• Condensation is the process during which water vapor changes into liquid water

The Nitrogen Cycle

Almost 80% of the air that you breathe is Nitrogen gas.

Nitrogen is an important element for life.

The nitrogen your body needs can only be obtained from plants.

TheNitrogenCycle

Plants cannot use pure nitrogen gas either.

Nitrogen must be broken down or fixed for plants to use it.

One method in which nitrogen gas is fixed is by bacteria in the soil that decompose dead plants and animals.

The second method is fixation through---

Lightning

Quick Quiz!

How is nitrogen fixed so that plants can use it for growth?

Nitrogen fixing bacteria

and

Lightning

Carbon Cycle

• Carbon is an element found in all living things

• It is through Carbon Dioxide Gas found in the atmosphere that carbon enters the living parts of an ecosystem

The Carbon Cycle

Photosynthesis

Plants use carbon dioxide to produce food in the form of a sugar called glucose- a process known as photosynthesis.

Food supplies the energy and materials living things need to live and grow

As a byproduct of this process oxygen is released to the atmosphere.

Quick Quiz

Plants produce their food in a process called?

Photosynthesis

Energy in Food

• To release the energy in food, organisms break down the carbon compounds, a process called respiration.

• Carbon is released and cycled back into the atmosphere as Carbon Dioxide

Quick Quiz!

Animals release the energy in food by a process

called?

Respiration

Carbon in Earth’s Oceans• Earth’s oceans contain far more carbon

than the air does.• In water ecosystems carbon dioxide is

dissolved in water• Marine animals also release Carbon

Dioxide into water from respiration• Algae and phytoplankton are

photosynthetic organisms that use carbon and sunlight to produce their own food

Quick Quiz!

What do organisms in the ocean require for photosynthesis?

Carbon

and

Sunlight

Greenhouse Effect• The Greenhouse Effect is

the trapping of heat in the atmosphere by gasses such as Carbon Dioxide and Methane

Math

Extension

Temperature and the Water Cycle

Remember the metric freezing and boiling points?

Answer the following1. A container of water is left out over

night, when the temperature is -18C. In the morning, the air temperature rises by 8C. What temperature is in the air. What will happen to the water.

2. An ice block sits in a field where the air is 0C.The air temperature rises by 16C, then it drops 8C. What temperature is the air in the field now. What will happen to the ice.

3. What happens to a block of ice after the temp. in the air follows this pattern: -6 +17+10+18+(-5)? What temp. has the air reached?

Answers

1. -18+8= -10C, the water will freeze

2. 0+16-8=8C, some of the block will melt

3. It melts, 34C

The

End