Learning Check 1

Epiphytes are smaller plants that grow on other plants, such as the ball moss that lives on a tree. The moss benefits from greater exposure to light and to nutrients from the air and rain. The moss does not harm the tree as it uses the tree only for support. The relationship is an example of -

• commensalism

• mutualism

• competition

• predation

Many ants live close to aphids, tiny insects that draw liquids from plants. The ant eats honeydew, a sugary liquid that aphids release. The ants also protect the eggs of the aphids. This relationship between ants and aphids is an example of -

• predation

• parasitism

• mutualism

• commensalism

A student eats only foods from plants, such as rice, beans, lettuce, and apples. Which trophic level does the student belong to?

• primary producer

• primary consumer

• secondary consumer

• tertiary consumer

Which food chain correctly illustrates the direction in which energy flows through an ecosystem?

• sunlight > scavengers > decomposers > producers > herbivores

• sunlight > producers > herbivores > omnivores > carnivores

• sunlight > producers > decomposers > herbivores > carnivores

• sunlight > herbivores > producers > carnivores > omnivores

A student created the food web of a Texas pond ecosystem shown. How should the web be modified to illustrate how matter cycles through an ecosystem?

• add arrows linking all the fish and the crayfish to a human consumer

• add arrows linking the fish, crayfish, and heron to a top predator

• add arrows linking all producers and consumers back to the crayfish

• add arrows linking all organisms back to scavengers or decomposers