Energy and Nutrient TransferFood chains and Food webs

Objectives:*Describe a food chain and each feeding stage in

it**Distinguish between a food chain and a food

web

Feeding relationships

USING YOUR OWN KNOWLEDGE AND THE TEXT BOOK FIND THE MEANINGS OF THE FOLLOWING WORDS:COMMUNITY, POPULATION,

1. Food chains show which organisms eat other organisms

2. Food chains always begin with producers (green plants) which provide food for consumers

3. The energy for the producer always come from the Sun

Food chainsFood chainsFood chainsFood chains

Food chains

Food Chains

Green plant

Plant eater

Meat eater

Producer

Herbivore

Carnivore

Producer

Primary consumer

Secondary consumer

Top carnivore Tertiary consumer

The direction of the arrow shows

the direction energy is passed

Food chainsFood chainsFood chainsFood chains

Food chains

1. Food chains can be connected together to form food webs

2. If the population of one species in a food web changes it can affect many other species’ populations.

Food websFood websFood websFood webs

Food webs

Food websFood websFood websFood webs

Food webs

Food websFood websFood websFood webs

Food webs

Pyramids of numbers and Biomass

Objectives:*Draw describe and interpret pyramids of numbers and pyramids of biomass**Compare pyramids of numbers and pyramids of biomassH/W due in on 11/11Draw two pyramids of numbers with different shapes. Explain their shapes.

1. A pyramid of numbers shows the relative number of organisms at each trophic level of a food chain but do not take the size of the organisms at each trophic level

2. A pyramid of biomass shows the amount of mass (or energy) at each trophic level of a food chain but do not indicate the rate of growth of the organism. Biomass varies with seasons.

3. Energy is lost at each stage of a food chain

Pyramid of Numbers & BiomassPyramid of Numbers & BiomassPyramid of Numbers & BiomassPyramid of Numbers & Biomass

Pyramid of Numbers & Biomass

TCSCPCP

No. of individual decreases

Pyramid of NumbersPyramid of NumbersPyramid of NumbersPyramid of Numbers

Pyramid of Numbers

Pyramid of NumbersPyramid of NumbersPyramid of NumbersPyramid of Numbers

Pyramid of Numbers

Pyramid of NumbersPyramid of NumbersPyramid of NumbersPyramid of Numbers

Pyramid of Numbers

Explain the shape of this pyramid

parasites

ladybirdsgreenfly

Rose bush

Pyramid of BiomassPyramid of BiomassPyramid of BiomassPyramid of Biomass

Pyramid of Biomass

Shortening the Food chain

Objectives:*Explain energy losses between trophic levels in food chains**Explain the increased efficiency in supplying green plants as human food compared to feeding crop plants to animals

Energy Pyramids

67

1600

14000

87000

Water weeds – tadpoles – small fish - pike

Wasted EnergyWhenever energy is transferred along a food chain, a lot of the energy is wasted at each stage in the food chain. For example when a leaf is eaten by a caterpillar, not all of the energy in the

leaf is passed to the caterpillar.

Energy wasted(90%) when leaf eaten by a

caterpillar

Energy transferred (10%)when leaf eaten by

a caterpillar

Energy transferEnergy transferEnergy transferEnergy transfer

Energy transfer

2-5%

2-5% absorbed by leavesRest reflected back

Explain the increased efficiency in supplying green plants as human food compared to feeding crop plants to animals.

Nutrient Cycles

Objectives:*Describe the role of bacteria and fungi in decomposition**Describe the different stages of water cycle

consumers

decomposers

Nutrients in environment

producers

1. Burning fuels, respiration, acid rain on certain rocks (e.g. limestone) release carbon dioxide into the atmosphere

2. Oceans and plant photosynthesis remove carbon dioxide from the atmosphere

The Carbon CycleThe Carbon CycleThe Carbon CycleThe Carbon Cycle

The Carbon Cycle

Carbon dioxide levelsCarbon dioxide levelsCarbon dioxide levelsCarbon dioxide levels

Carbon dioxide levels

The Carbon CycleThe Carbon CycleThe Carbon CycleThe Carbon Cycle

The Carbon Cycle

1

2 346

5

Animal Respiration

Bacterial Respiration

Atmospheric carbon dioxide

Plant Respiration

Combustion

Photosynthesis

Animals Dead organisms

Green plants

Wood, peat, oil and coal

The Carbon Cycle

1. Copy this diagram out adding pictures and as many equations as you can.

2. Why are microbes so important in the recycling of carbon?

3. Why are plants so important in the recycling of carbon?

4. In which four ways are carbon atoms returned to the atmosphere as carbon dioxide?

5. Which of the numbered arrow has changed most in the last 50 years?

Water Cyclehttp://www.educationalrap.com/song/water-cycle.html

The Nitrogen cycle

Objectives:*Describe the roles of microorganisms in the nitrogen cycle**Describe the absorption of nitrate ions by plants and their use in making proteins that enter food chains

http://www.clickbiology.com/video-nitrogen-cycle/

1. Plants and animals need proteins for growth and repair

2. Animals eat plants for their supply of protein

3. Plants absorb nitrates from the soil for their supply

4. Nitrates in the soil can be replaced by crop rotation, using fertilisers or, occasionally, by lightning

The Nitrogen CycleThe Nitrogen CycleThe Nitrogen CycleThe Nitrogen Cycle

The Nitrogen Cycle

MicroorganismsMicroorganismsMicroorganismsMicroorganisms

Microorganisms

The Nitrogen CycleThe Nitrogen CycleThe Nitrogen CycleThe Nitrogen Cycle

The Nitrogen Cycle

The Nitrogen CycleThe Nitrogen CycleThe Nitrogen CycleThe Nitrogen Cycle

The Nitrogen Cycle

The Nitrogen CycleThe Nitrogen CycleThe Nitrogen CycleThe Nitrogen Cycle

The Nitrogen Cycle