Food Web Energy Transfer

Nutrient & Energy Transfer

How organisms gain & pass on energy

• As discussed, food webs are interconnecting food chains for multiple organisms

• However, they're also a map of how energy & nutrients get passed along

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Food webs

Match

Match the trophic level with the producer/consumer

• Trophic Level 1

• Trophic Level 2

• Trophic Level 3

• Trophic Level 4

• Trophic Level 5

Energy producer

Primary Consumer

Secondary Consumer

Tertiary Consumer

Apex Predator

• Energy producer

• Primary Consumer

• Secondary Consumer

• Tertiary Consumer

• Apex Predator

Food webs show the direction energy moves; the arrows indicate the flow of an organism's energy from one trophic level to another.

• Ex: the shark eats the tuna, gaining energy

Energy flow

Match

Match the producer/consumer level with what they eat

• Producers

• Primary Consumers

• Secondary Consumers

• Tertiary Consumers

• Apex Predators

Sun, water, CO2

Herbivores

Carnivores

Omnivores

Can eat anything below them

• Sun, water, CO2

• Herbivores

• Carnivores

• Omnivores

• Can eat anything below them

Multiple Select

Which trophic level organisms do you think have the most available energy to them (opinion)?

• 1: Producers

• 3: Secondary Consumers

• 2: Primary Consumers

• 5: Apex Predators

• 4: Tertiary Consumers

The energy in food is measured in Kilocalories; 1000 calories.

• This is the amount of energy it takes raise the temperarture of 1kg of water 1 degree (Celcius)

• Food labels are in Kcal; you need between 1500 - 3000 Kcal a day (depending on gender, age, and muscle mass)

Energy Measurement

Energy producers - plants - typically have the most available energy to them.

• The sun is consistent and constant, and plants use that to power photosynthesis

Energy Creation

Movin' on up

Multiple Choice

How many Kcal will it take to move 1kg of water 5 degrees Celcius?

• 5 Kcal

• 5,000 Kcal

• 1,500 Kcal

• 1,000 Kcal

Energy dropoff

• Available Kcal decreases every time you move up a trophic level

• Only about 10% of energy in an organism is gained by eating it

• Ex: There could be a total of 1,000 Kcal in a bowl of lettuce. If you eat it, your body only gains 100 Kcal

• This is ten percent PER LEVEL increase; so if a fish eats a 100 KCal mayfly, and you eat that fish, you only gain 1 Kcal worth of that bug's energy! (100 x 0.1 x 0.1 = 1)

Multiple Choice

How much energy is passed along every trophic level increase?

• 50%

• 25%

• 100%

• 10%

Math Response

A field mouse gains 100Kcal of energy from eating berries; how many of these Kcal will transfer to a fox if it eats the mouse?

Type answer here

Correct Answer: 10

Deg^°

Rad

Multiple Choice

A gopher has gained 200 Kcal from eating grass all day. A snake comes along and eats that gopher, gaining a portion of those Kcal. A hawk swoops down and eats the snake; how many trophic levels have we moved up?

• 2

• 3

• 4

• 5

Math Response

A gopher has gained 200 Kcal from eating grass all day. A snake comes along and eats that gopher, gaining a portion of those Kcal. A hawk swoops down and eats the snake; how many Kcal from the grass is transferred to the hawk?

Type answer here

Correct Answer: 2

Deg^°

Rad

SImilar to a food chain or web, energy pyramids are a diagram that show us the amount of energy that moves from one trophic level to another

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Energy Pyramid

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Then, organize your organism's food web into an energy pyramid. Make this look good!

Your organism

Organize the food web on slide 9 of the Jamboard (Food Network) into an energy pyramid; most energy on bottom, least on top!

Jamboard

Practice this

All done?

Progress reports are coming

I'd work on any missing work for other classes or mine. Tomorrow we'll have some makeup quiz days, as well as a quiz over this material so far.