Cycles of Matter

Essential Question:How are the materials needed for life recycled

and reused in nature?

1. Why is carbon especially important to living things?

• Key ingredient in living tissue• “backbone” of all molecules that make up living things

Carbon atom

Glucose molecule: the sugar plants make in photosynthesis

The Carbon Cycle

CO2 in atmosphere

photosynthesis

respiration

Decomposition(dying)

feeding

Human activity

Fossil fuels

Photosynthesis(phytoplankton) respiration

Volcanic activity

Decomposition(dying)

(Coal, oil, gas)feeding

0.04%

1. Take out this assignment. 2. Get a computer and start logging on…..

2. Describe how carbon is recycled and re-used by living things in an ecosystem. Be sure to use the following terms in your description: photosynthesis, respiration, decomposition, feeding.• Plants take in carbon dioxide for photosynthesis.• Animals breathe out carbon dioxide in respiration.• When animals and plants die, their bodies decompose, and the carbon in them

goes into the ground.• Animals take in carbon from the plants and animals they feed on.

Suppose there was a the chipmunk population was wiped out by disease in the forest ecosystem shown below. Identify another organism in the forest ecosystem and describe how its population could be limited by the disappearance of chipmunks.

• Coyote population would be limited because fewer chipmunks to eat.

• Same for skunks and owls.

3. Energy transformation = changing energy from one form to another. How is energy transformed in the carbon cycle?

In photosynthesis, light energy is changed into chemical energy (sugar)

Photosynthesis

Sugar(chemical energy)

4. Energy transfer = energy from one living thing is given to another. How is energy transferred in the carbon cycle?

Energy is transferred when animals eat plants or other animals.

Energy = the capacity of a physical system to perform work. Energy exists in several forms such as heat, kinetic or mechanical energy, light, potential energy, electrical, chemical, or other forms.

• Energy transformation = changing energy from one form to another.

• Energy transfer = energy being passed from one thing to another.

Matter = carbon, nitrogen

• Matter transformation = changing matter from one form to another.

• Matter transfer = matter being passed from one thing to another.

5. Describe one way animals take carbon in from their environment and two ways they put carbon out into their environment.

• Take carbon in by eating other animals or plants.• Put carbon out by breathing out, exhaling (respiration)• Put carbon out by dying and decomposing.

6. Describe one way plants take carbon in from their environment and one way they put carbon out into their environment.

• Plants take in carbon dioxide by photosynthesis.• Carbon in their bodies goes into ground by dying and

decomposing.

7. Why do all living things need nitrogen?

• Used to make protein• Proteins make up

muscle and other tissues.

The Nitrogen Cycle

N2 in Atmosphere

Nitrogen fixation (bacteria)

Uptake by producersDecomposition

Denitrification (bacteria)

Reuse by consumers (eating)

78%

Excretion (poop)

8. Describe how nitrogen is recycled and re-used by living things in an ecosystem. Be sure to use the following terms in your description: nitrogen fixation, decomposition, excretion, uptake by producers, reuse by consumers.• Bacteria use nitrogen fixation to change nitrogen from the air into a form living things

can use to make proteins.• Nitrogen that’s been fixed by bacteria is taken up by producers.• Nitrogen in plants is eaten by animals (reused by consumers).• When animals poop, the nitrogen in their poop (excretion) goes into the ground.• When animals and plants die, their bodies decompose and the nitrogen in them goes

into the ground.

9. Describe one way that animals take nitrogen in from their environment and two ways they put nitrogen out into their environment.

• Take nitrogen in by eating plants or other animals.• Put nitrogen out by dying and decomposing• Put nitrogen out by pooping.

10. Describe one way plants take nitrogen in from their environment and one way they put nitrogen out into their environment.

• Plants take in nitrogen from soil through their roots.• Put nitrogen out by dying and decomposing.

Questions?

Make-up Tasks

• Banana Slugs– Q1: Planning a Controlled Experiment(Q’s 4 & 5)– Q2: Cycles of Matter (Q’s 3-6, 9 & 10)– Q4: Evolution & Natural Selection (Q’s 9 & 10),

see “niche” in slideshow• Invasive Crayfish– Q2: Models & Human Impact (Q’s 1,3) and Forest

Food Webs (Q’s 6 & 7)– Q4: Models & Human Impact (Q’s 5,6, & 7)