Warm up 4/8

Energy Flow

Without a constant input of energy, living systems cannot function.

Producers

Producers are organisms that capture energy and use it to produce food from inorganic compounds

Producers are also called autotrophs, meaning they can make their own food

Types of Producers

Photoautotroph– organism that uses light energy to power chemical reactions that convert carbon dioxide and water into oxygen and energy rich carbohydrates (photosynthesis)

Chemoautotroph – organism that make organic carbon molecules from carbon dioxide using energy from chemical reactions (chemosynthesis)

Photosynthesis Chemosynthesis

Consumers

Organisms that rely on other organisms for their energy and food supply because they cannot harness energy directly from the physical environment.

Consumers are also called heterotrophs.

Types of Consumers Herbivores – obtain energy by eating only

plants

Carnivores – obtain energy by eating only animals

Omnivores – obtain energy by eating plants and animals

Types of Consumers Detritivore – obtain energy by

feeding on plant and animal remains and other dead matter

Decomposers – obtain energy by breaking down organic matter

Feeding Relationships

The relationships between producers and consumers connect organisms

into feeding networks based on who eats whom.

Food Chain A series of steps on which organisms

transfer energy by eating and being eaten.

Food Web Links all the food chains in an

ecosystem together forming a network of complex interactions

Trophic Levels

Each step in a food chain or food web

Producers make up the first trophic level and consumers make up the second, third or higher.

Each consumer depends on the trophic level below it for energy.

Ecological Pyramids

A diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web

Ecologists recognize three types of pyramids: energy, biomass and numbers

Energy Pyramid

Only about 10% of the energy available within one trophic level is transferred to organisms at the next trophic level

Part of the energy is lost to the original organism using it. Part of the energy is lost as heat.

Biomass Pyramid

The total amount of living tissue within a given trophic level

Usually expressed in terms of grams of organic matter per unit area

Pyramid of Numbers

The numbers of individual organisms at each trophic level

Ecology: Feeding Relationships

Energy flows through an ecosystem in one direction (arrows) from the sun or inorganic compounds to producers to consumers.

Food chain: diagram that shows simple feeding relationships.

Trophic level: each step in a food chain

All food chains start with a producer.

Feeding Relationships: Food Chain

squid (tertiary consumer)

small fish (secondary consumer)

zooplankton (primary consumer)

algae (producer)

Students be careful!

Remember: the arrow

shows the directionenergy flows in an ecosystem.

In this example, the

Leopard seal eats the

penguin and as a result,

gets the energy.

Ecology: Feeding Relationships

A food web is a network of complex feeding relationships that connects multiple food chains.

If one species is lost from a food web, all other species are affected.

Analyze this food web!

What does the mouse receive energy from?

What level consumer is the frog?

Where does the rabbit’s energy go?

How many levels does the mouse occupy?

You will be graded on accuracy, neatness, effort, ability to follow directions and organization.

Take your time to lay out your squares before you glue down your organisms or draw your arrows.

Group Food Web Activity

The food web must have a key that includes the type of organisms in your web

(Color the organism accordingly) Producers – green Carnivores – red Herbivores – orange Omnivores – blue Decomposers - brown

You may organize your food web any way you like – but it does need to be organized and make sense!

Make sure your arrows are pointing the right direction – the arrow points in the direction of energy flow.

Directions for Food Web