Review 2 ch 4&5 energy and population

Which is the most likely reason the population is remaining nearly constant after Phase II?

• They have eaten all their food.

• They have reached their carrying capacity.

• The death rate increased while the birth rate remained constant.

• They have a new predator.

There is a forest of nearly 1000 spruce trees. Which of the following events would have the LEAST effect on the forest’s carrying capacity for the trees?

• A beetle that infects spruce trees is introduced to the land.

• Human activities drain about half of the water that the land generally receives.

• Maple trees are introduced to the land, where they grow well.

• About one third of the trees are cut down and hauled away.

A tropical rainforest has a large amount of biodiversity. Which of these events is MOST LIKELY to threaten the biodiversity of the forest?

• a 20 percent increase in the population of one of the native species

• the arrival of migrating birds that prey on the insects

• the introduction of a nonnative species that has no natural enemies in the forest

• a strong storm that blows down many of the older trees

• a typical dry season with less rain than the wet season

Giant Atlantic bluefin tuna where harvested (fished) to drastically low numbers over the last 100 years. Which statement best explains why that was possible?

• The death rate from fishing was much greater than the natural reproductive rate.

• The death rate from fishing was much greater than the natural death rate.

• The fishing only removed older individuals.

• The fishing removed both male and females equally.

One biotic factor that affects consumers in an ocean ecosystem is

• temperature variation

• salt content

• pH of water

• an increase in phytoplankton

Which of the following is beneficial to the growth of plants?

• Soil bacteria that perform photosynthesis

• Soil bacteria that perform chemosynthesis

• Soil bacteria that perform nitrogen fixation

• Soil bacteria that perform denitrification

Autotrophs are classified in to two groups according to which of these properties?

• Energy source, either sunlight of chemicals

• water quality, either fresh water or salt water

• food quality, either living matter or dead matter

• food type, either plant matter or animal matter

Which would be the most likely primary producers in an open ocean food web?

• Phytoplankton

• Floating plants

• Zooplankton (animal like plankton)

• Plants living on the ocean floor.

Which statement is true?

• An organism can be in in many food webs but only one food chain

• An organism can be in many food chains but only one food web

• Both

• Neither

The model showing how nitrogen moves in an ecosystem is what type of model?

• Geological system

• Food web

• Biogeochemical

• Energy pyramid