Bio Chapter 37 HW

10,000 kcal of producer could support approximately _____ kcal of tertiary consumer.

10

Approximately _____% of the energy at one trophic level is passed on to the next highest trophic level.

5-10

In an ecosystem where 500,000 kcal of sunlight is available for producers, approximately how much chemical energy will be contained in secondary consumers?

50 kcal

Assimilation is indicated by the letter(s) _____.

A

Which of the following people is likely at the greatest risk if they are infected with Toxoplasma gondii?

A person with HIV, which affects the immune system.

Which of these research topics would be considered an example of community ecology?

A researcher found that the reproductive success of bumblebees decreased when the population density of honeybees increased. The decline in the number of bumblebees appeared to be a result of competition for nectar.

Which of the following is most likely to suffer the most from invasive species?

A species found only on the island of Hawaii.

Nitrification is indicated by the letter(s) _____.

B

_____ are secondary consumers.

Carnivores

Which of the following invasive species is most likely to be deemed harmful by all scientists.

Chestnut blight in the United States.

Due to an increased risk of infection by Toxoplasma gondii, which of the following would be best for a pregnant woman to avoid doing?

Cleaning a cat's litter box.

A study of metabolic rates in a terrestrial community showed that the energy released by respiration exceeded the energy captured in photosynthesis. Which of the following situations is most likely?

Community biomass is decreasing.

If the niches of two species are very similar, which of the following is true?

Competition between the two species will be severe.

Nitrogen-fixing bacteria is(are) indicated by the letter(s) _____.

D and E

Which of the following is true around the world?

Flora and fauna are more homogenous now than in the past.

Consider the following prairie food chain. Tall grass is consumed by grasshoppers that, in turn, are eaten by mice, and the mice are eaten by prairie kingsnakes. Red-tailed hawks prey on mice and prairie kingsnakes. When a red-tailed hawk dies, bacteria, beetles, fungi, and many types of worms help break down the body. Which of the following correctly identifies a trophic level in this ecosystem?

Grasshoppers are primary consumers.

Which of the following is true?

It is possible for a species to be endangered in its natural habitat and considered a pest in another habitat.

Which one of these is a nitrite?

NO2 -

_____ removes nitrogen from the atmosphere.

Nitrogen fixation

Which of the following is an example of mutualism?

Some biologists have observed Egyptian Plovers, a type of bird, land on the open mouth of a Nile crocodile without being eaten and remove leeches stuck firmly to the crocodile's gums.

Which of the following is an example of herbivory?

Squirrels in the forests of Wisconsin hide away hickory nuts and acorns, which they will eat during the long, cold winter.

You are a wildlife ecologist interested in finding out if Toxoplasma gondii impacts the predator/prey relationship of the Canada lynx and snowshoe hare. If it does, which of the following would be true?

The parasite would affect the brain of the hare.

In almost all food webs, the top trophic level of consumers is quaternary (fourth). Why are fifth-level consumers very rare?

There is rarely enough available energy to sustain a fifth trophic level.

Which of the following best describes an example of a community experiencing secondary succession?

This community of grasses began growing after a fire killed the trees and shrubs previously at this site.

In a typical terrestrial ecosystem, energy input comes directly from the sun, and it is converted to chemical energy through photosynthesis. Interestingly, an unusual ecosystem can exist in the absence of sunlight. What could be the source of energy?

This ecosystem could be powered by chemical energy obtained from inorganic compounds.

Without elephants, some of the grasslands in Africa would eventually become thickets or forests because elephants weed out trees and shrubs. Even though elephants make up a small percentage of the animals living on the grassland, the grassland would eventually cease to exist without them. In this community, elephants are __________.

a keystone species

Which of these removes carbon from the atmosphere?

algae

Nitrifying bacteria convert _____ to _____.

ammonium ... nitrites

Aquatic nitrate pollution can result in _____.

an algal bloom that, when the algae die and are decomposed by bacteria, leads to hypoxia and the death of fish

Which of these are the two major sources of nitrate pollution in rivers?

animal wastes and fertilizers

The phosphorus cycle lacks a(n) _____ component.

atmospheric

Your friend works for a pharmaceutical company trying to develop a drug to eliminate dormant Toxoplasma gondii cysts in humans. Which of the following is/are the target?

brain

Controlling which of the following from early on would have benefitted the birds of Guam?

brown tree snake

Examine the figure, which shows a food web. If the Western diamondback snake population were suddenly reduced because of a virus that kills only snakes, we would expect that the population of __________.

cacti would suffer from increased herbivory

Flounder look like the sea floor. This is an example of _____.

camouflage

You are a veterinarian interested in finding out the percentage of cats in your area that are infected with Toxoplasma gondii. Which of the following should you test for oocysts of this organism?

cat feces

A series of reciprocal evolutionary adaptations in two species is called _____.

coevolution

Humans and sharks both eat fish. Which of these terms applies to the relationship between the human and the shark?

competition

The figure below indicates that the primary role of decomposers is to __________.

contribute to the abiotic reservoir through nutrient cycles

Detritus is composed of _____.

dead organic matter and excreted wastes Submit

What name is given to the process by which detritivores return carbon to the atmosphere?

decomposition

Soil erosion in Haiti is caused largely by _____.

deforestation

An earthworm that feeds on the remains of plants and animals is acting as a _____.

detritivore

Succession of communities occurs because _____.

each existing community changes the environment

What generally flows in one direction through an ecosystem, from producers up through each level of consumers, and is not recycled?

energy

A species of malaria-carrying mosquito lives in a forest in which two species of monkey, A and B, coexist. Species A is resistant to malaria, but species B is not. The malaria-carrying mosquito is the chief food for a type of bird in the forest. If all these birds were suddenly eliminated by hunters, which of the following would be an immediate observable consequence?

increased mortality in monkey species B

Humans who have pets tend to be healthier than humans who do not have pets. Which of these terms applies to the relationship between a human and a pet?

mutualism

In tropical forests, there are plants known as ant-plants. These plants host ant colonies. When the ant colony is the species Petalomyrmex phylax, the presence of the ants protects the ant-plants from predation by herbivores. However, the ant species Cataulacus mckeyi takes advantage of the nesting place and nectar the plants provide without affording any protection to the plant. The interspecies interaction between the ant-plants and P. phylax is an example of __________, whereas the interaction between the ant-plants and C. mckeyi is an example of __________.

mutualism; parasitism

Denitrifying bacteria convert _____ to _____.

nitrates ... nitrogen gas

Some bacteria in the _____ cycle are symbiotic with the roots of legumes.

nitrogen

Eutrophication (excessive algal growth resulting in decreased concentrations of dissolved oxygen) in lakes is frequently the direct result of _____.

nutrient enrichment (nitrate and phosphate runoffs from land)

Which of these terms applies to the relationship between a dog and a blood-sucking tick?

parasitism

A human eats a deer. Which of these terms applies to the relationship between the human and the deer?

predation

A cow eating grass is an example of a _____.

primary consumer

In an ecosystem, phytoplankton are _____.

producers

Consider this segment of a food web: Snails and grasshoppers eat pepper plants, spiders eat grasshoppers, shrews eat snails and spiders, owls eat shrews. The shrew occupies the trophic level(s) of __________.

secondary and tertiary consumers

When a human eats a steak, the human is acting as a _____.

secondary consumer

Which of the following is an abiotic reservoir?

soil

Species richness and relative abundance taken together define the __________ of a community.

species diversity

A human who just ate a hamburger is eaten by a shark while swimming. The shark is acting as a _____.

tertiary consumer

The main cause of the recent increase in the amount of carbon dioxide in Earth's atmosphere is __________.

the burning of larger amounts of wood and fossil fuels