QUIZ 15 QUESTIONS

Coastal regions of the ocean have high primary productivity. What is the primary reason for this pattern?

- Upwelling of nutrient-rich deep waters commonly occurs along continental margins. - Sunlight is able to penetrate coastal waters, so photosynthetic rates are high among autotrophs. - Erosional runoff from continents supplies abundant nutrients.

How many kilograms of biomass at the primary producer level would be required to support 20 kilograms of biomass at the tertiary consumer level?

20,000

How many "cells" of circulating air are found around the Earth?

6

Most deserts occur at approximately 30° latitudes. Which of the following statements BEST reflects this finding?

Cool dry air descends at 30° latitude.

As air moves from the base up the side of a mountain, it cools. What is one consequence of this movement of air?

Moisture will drop as rain as the air moves up the side of the mountain.

Primary producers are present in every biome, including the deep sea. How can there be primary producers in the deep sea when sunlight does not penetrate to these depths?

Primary producers in the deep sea use energy from chemical reactions to drive the reduction of CO2 to organic compounds.

When sea otters are present in a kelp forest community, there are more than 12 species in the community. If sea otters are removed, there are 5-7 species that remain in the community. These data suggest that sea otters are:

a keystone species

Temperature differences on Earth are caused primarily by the:

amount of solar energy received per unit area at each latitude.

On land, _____, which are broad, ecologically uniform areas, are recognized by their characteristic vegetation that reflects adaptation of form and physiology to climate.

biomes

When two species compete for resources, the fitness of:

both species will decline

Autotrophs remove _____ from the air and fix this into tissues providing _____ for secondary consumers.

carbon dioxide; energy

Spanish moss is not a moss, but a flowering plant (Tillandsia usneoides) often seen draped from the branches of live oaks, cypress, and other large trees in the southeastern United States. The trees on which it grows provide support but no nutrients or moisture—the plant provides those things for itself, without apparently harming its support tree. This, then, is an example of a:

commensalism

Which group in a food web is responsible for returning inorganic compounds back to the environment?

decomposers

Glacier Bay in Alaska is a fjord whose lowlands were covered by glacial ice until around 230 years ago. As the glacier retreated, it left behind sediment that was exposed to plant colonization; remarkably (and fortunately for generations of ecologists), the location of the tip of the retreating glacier has been frequently documented since the late 1700s. This means that scientists have been able to develop a detailed timeline of the changes in the plant community, or _____ in Glacier Bay over time.

ecological succession

Tropical leafcutter ants collect leaf cuttings which they transport to special underground chambers. There, they chew the leaves to create nursery beds on which they grow a species of fungus they use for food. When ant queens disperse to establish new colonies, they carry the fungus with them, dispersing it as well (this benefits the fungus). In the ants' nest, the fungus is at risk of being destroyed by another fungal species that is able to grow in the same habitat, using the same limited resources. On their bodies, the ants carry and provide a home for bacteria that produce antibiotics the ants use to kill this second fungus and thereby protect their food supply. In this system, the relationship between the two fungal species is:

interspecific competition

Banner-tailed kangaroo rats, Dipodomys spectabilis, are rodents that feed on seeds and are endemic (found only in) to the deserts of the southwestern United States. Which of the following is the BEST description of their niche?

seed-eating rodents that can tolerate the intense heat and dryness in the southwest deserts

In a pond, tadpoles eat algae and fish eat the tadpoles. Around the pond, grasshoppers eat grass and, at night, are preyed upon by bats. Other bats eat the fish that eat the tadpoles. In this community, the fish-eating bats are:

tertiary consumers.

Primary producers are the basis for all aquatic and terrestrial food webs. How does the amount of primary production affect community structure?

the more energy available from primary producers, the more individuals that could be supported at higher trophic levels in the community

If the Earth spun on an axis that was perfectly perpendicular to the equator:

there would be no seasonality in climate.