Unit 3: EcosystemsUnit 3: EcosystemsChapter 6 – Part 1Chapter 6 – Part 1

Pg. 92-95Pg. 92-95

3.1.1 Define Ecosystem

Ecosystem = the network of relationships (interactions) among plants, animals (living) and the non-living parts in an environment.

3.2.1 Producers

Producer = a plant which can synthesize carbohydrates using carbon dioxide and the sun’s energy.

“Produce” their own food AND food for the rest of the ecosystem

Other examples:GrassesTrees shrubsWater liliesFlowersVegetablesFruits

Consumers = All those organisms that have to eat (consume) plants or animals to obtain their food.

3.2.1 Consumers

Types of consumers

Primary Consumers: Animals that eat producers. Also called 1st. order consumers or herbivores. (Ex. Rabbit, squirrels, grouse, insects)

Secondary Consumers: Animals that eat primary consumers. Also called 2nd. order consumers or carnivores. (fox, owl, mink )

Tertiary Consumers: Animals that eat secondary consumers. Also called 3rd. order consumers or carnivores. (Wolf, coyote, hawk)

Omnivores: Animals that eat both producers (plants) and consumers (animals).

• Decomposers = Simple organisms that obtain their food from dead/decaying organisms and wastes.

3.2.1 Decomposers

Examples:WormsBacteriaFungiProtozoa

Identify;Identify;ProducersProducers

HerbivoresHerbivores

CarnivoresCarnivores

OmnivoresOmnivores

What’s missing?What’s missing?

Decomposers!Decomposers!

3.2.3 Food chain

Food chain = linear sequence representing the flow of nutrition from the simplest plant to the top carnivore.

Ie. What eats what??

3.2.4 Food web

Food web = a series of interconnecting food chains in an ecosystem.

Shows all possible flows of nutrition.

Much more complicated!!

Food Chain vsvs Food Web

Identify examples of producers & consumersSee “Handout”

Producers

Primary Consumers / herbivores

Secondary Consumers / Carnivores

Tertiary Consumers / Carnivores

Decomposers

Shrubs, grass, trees

Grasshopper, rabbit, deer

Mountain lion, snake, shrew, insect-eating bird, hawk

Hawk, snake, mountain lion

Bacteria, fungi

Give an example of a food chain from figure to the right.

Note: The arrows indicate the flow of energy & nutrients from one level to the next

Tree

→

insect

→

insect eating bird →

hawk

Producer Primary consumer

2nd order consumer

3rd order consumer

Sample Food Chain

Draw an example of a food web containing humans.

MosquitoHawkCow

GrassMan

WormsPhytoplankton

Fish

Draw an example of a food web containing humans.

ManCow

Mosquito

Hawk

Phytoplankton

fish

Grass Worms

Using a diagram, describe the relationship Using a diagram, describe the relationship between latitude and the sequence of between latitude and the sequence of ecosystems.ecosystems.

Using a diagram, describe the relationship Using a diagram, describe the relationship between elevation and the sequence of between elevation and the sequence of ecosystems. (a) ecosystems. (a)