Chapter 24: Interactions of Life

Which of these organisms is a producer?

• trout

• fern

• bear

• snake

Answer explanation

A fern is a producer because it uses photosynthesis to make its food.

Cactus plants are usually in which environment?

• aquatic regions

• arctic regions

• tropic rain forest regions

• desert regions

A salamander's habitat is which of these?

• the arctic region

• a hollow cactus

• the ocean

• a forest floor

Answer explanation

The forest floor is the salamander's habitat because it provides food, shelter, and the right temperature and moisture conditions for it.

______________ limits population size.

• Symbiosis

• Mutualism

• Competition

• Parasitism

All populations living together in an ecosystem are called a ____________.

• community

• biosphere

• sample count

• predator

Which of these limits the size of a population?

• an increased amount of water

• an increase in the number of prey

• a decrease in competition

• a reduction in living space

Answer explanation

When all the living space in an ecosystem is filled to capacity, a population's growth is greatly limited.

Which of these is a method used to count the size of a population in a large area?

• photosynthesis

• ecology

• sample counts

• population density

Answer explanation

The size of a large population can be estimated by multiplying the number of animals in a small region by a number that factors the size of the entire area.

Which of these factors helps a population grow?

• limited living space

• reduced amount of food

• increased numbers of predators

• plenty of water

Answer explanation

Having enough water is one competition factor that would allow a population to continue to grow.

A population of wolves lives in a region with plenty of food, water and living space. Which of these is true?

• The wolf population lives in a poor habitat.

• The wolf population faces increased competition.

• The wolf population will become carnivores.

• The wolf population has excellent biotic potential.

Answer explanation

The wolf population's biotic potential is great because there seems to be a few limiting factors.

You decide to raise mealworms in two identical containers at home. You count the number of mealworms in each container to compare _______________.

• homeotasis

• parasitism

• the death rate

• population densities

Answer explanation

Population density is one way to measure the size of a group of organisms.