Biology retake test

A disease resulting in the deaths of one third of a dense population of bats in a cave would be a

density-dependent limiting factor.

Which of following organisms is an omnivore?

Small fish

What percentage of energy is typically transferred between trophic levels?

10%

In what trophic levels is the songbird?

2 and 3

The graph shows the changes in a mosquito population. What caused the changes seen in the graph?

A density-independent limiting factor

Which of the following statements are true of introduced/ invasive species when they enter a community? I. Usually exhibit rapid growth II. Lack limiting factors such as predators III. Have reached carrying capacity IV. Can cause the extinction of native species

I, II and IV only

A toxin has entered the North Atlantic Ocean Community. What organism, in the the food web that you filled in above, would have the greatest concentration of toxin in their system as a result of biological magnification?

Shark

Using the figure above, predict what would happen to the wolf population in 2000.

It would decrease because the moose population is decreasing.

Female blue whales reach reproductive maturity at 10 years of age. Blue whales are pregnant for a year, and they give birth every two to three years. The babies are nursed for six months, and they stay with their mothers for a year. What type of species are blue whales?

K-strategists

What explanation fits the growth model portrayed in the graph?

Limits to resources exist for a population

How is parasitism different from commensalism?

One organism is harmed in parasitism and no organisms are harmed in commensalism.

Using the figure above, what is the most likely cause of the decrease in moose population immediately after 1995?

Overcrowding caused competition in the moose population

Which of the following descriptions about the organization of an ecosystem is correct?

Species make up populations, which make up communities.

Predict what would happen in the population if the bird species shown in the ecosystem above were to suddenly decrease.

The fish population would increase.

The graphs above show population growth of two species of paramecium. What is the most likely reason why the population of P. caudatum decreased in Graph III?

The two species occupy the same niche and P. caudatum is not able to survive.

The graph shows changes in a population of shrimp over time. Which conclusion is supported by this data?

This population of organisms lives in a stable environment and reached their carrying capacity.

Using the figure above, which of the following best describes the relationship between the wolves and moose?

Wolves are a natural predator for moose, and therefore keep their populations in check.

When the Mount St. Helens volcano erupted, the blast covered much of the surrounding area with ash. Based on the diagram, which list shows the sequence of succession that followed that eruption?

Z, X, Y, W

What organisms are primarily responsible for denitrification and nitrogen fixation in the figure above?

bacteria

Matter can recycle through the biosphere because

biological systems do not use up matter, they transform it.

The lowest level of environmental complexity that includes living and nonliving factors is the _____.

ecosystem

Suppose that a species of toads is introduced into a new environment in an attempt to reduce the population of insects. The toad has no natural predators in its new environment. The toad population will most likely

increase exponentially

As DDT (a pesticide) moves up the trophic levels in food webs, its concentration _____.

increases

The number of trophic levels in an ecological pyramid

is limited by the amount of energy that is lost at each trophic level

Some organizations are buying up sections of forest land. Once purchased, these sections of forest will never be cut down. The main reason for protecting these sections of forest is to

maintain the diversity of the living environment

A symbiotic relationship in which both species benefit is

mutualism

The symbiotic relationship between a flower and the insect that feeds on its nectar is an example of

mutualism- the flower provides the insect with food, and the insect pollinates the flower

Part of the nitrogen cycle is pictured here. The arrow labeled A represents the process of _____.

nitrogen fixation

Several species of warblers can live in the same spruce tree ONLY because they

occupy different niches within the tree.

Drought is considered a density-independent limiting factor because

population size does not impact the chance of drought.

A forest fire destroys the majority of the trees in a state park. Which effect will this most likely have on secondary consumers in that ecosystem?

the amount of available energy will decrease because fewer primary consumers will survive the lack of vegetation

If the population of mice is reduced by disease, which change will most likely occur in the food web?

the cricket population will increase

Which of the following is a density-independent limiting factor?

the eruption of a volcano