ECOLOGY 2

Approximately what percent of the potential energy available at one trophic level is passed on to the next trophic level?

• 80 – 95%

• 50 – 65%

• 25 – 40%

• 5 – 20%

An organism’s “trophic” level refers to ______________.

• the rate at which it uses energy

• where it lives

• what it eats

• whether it is early or late in ecological succession

A symbiotic relationship in which both species benefit is best described as _____?

• commensalisms

• competative exclusion

• mutualism

• parasitism

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

• Mutualism because the flower provides the insect with food and the insect pollinates the flower.

• Parasitism because the insect lives off the nectar from the flower

• Commensalism because the insect does not harm the flower and the flower does not benefit from the relationship.

• Predation because the insect feeds on the flower

All of the following statements about the diagram below are correct EXCEPT

Grass ----> Mouse ----> Snake ----> Owl

• The mouse is a herbivore

• The mouse is at higher trophic level compared to owl

• The snake is at the third trophic level.

• All of the organisms except grass are consumers

Which of the following best explains why there are seldom more than five trophic levels in a food chain?

• Most carnivores function at more than one trophic level.

• Trophic levels above this number contain too many individuals

• Top carnivores are too few in number to prey effectively

• Energy is lost from each trophic level.

Which of the following is true about secondary consumers in an ecosystem?

• They eat only plants.

• They are eaten by primary consumers

• They are smaller and weaker than primary consumers

• They are fewer in number than primary consumers

When there is an environmental resistance,

• the population will grow unlimitedly

• an ideal condition is achieved.

• an exponential growth curve will be obtained

• a sigmoid growth curve will be obtained

The maximum number of individuals that can be supported by a  particular area is a called

• Biotic potential

• Emigration

• Survivorship

• Carrying capacity

Which of the following statements are TRUE?

I.    Natality = mortality, population is stable

II.     Mortality > natality, population size decreases

III.   Natality > mortality, population size increase

IV.   Natality < mortality, population size increase

• I, II and III only

• I and III only

• I, II and IV only

• I, II, III and IV