Ecological interactions and Population Dynamics Quiz

What causes competition to occur in an environment?

• Good conditions make resources plentiful.

• Organisms struggle for a limited resource.

• Members of a population have different roles.

• A population falls below the environment’s carrying capacity.

Without other changes to a population, which of the following will cause a population to increase in size?

• The birth rate equals the death rate.

• The birth rate is less than the death rate.

• The birth rate is greater than the death rate.

• The birth rate and the death rate both equal 0.

Which of the following is an example of an abiotic limiting factor on population size?

• water availability

• Availability of food

• disease

• predation

When individuals join a population

• Aliens
• migration
• Immigration
• Emigration

Carrying Capacity is

• the capacity of what one person can carry per day 
• how many animals you have in your daily bag limit at the end of the year
• wildebeest at a watering hole with zebras
• the maximum number of individuals that the environment can support

The graph below shows the changes in the population size of a mammal species introduced onto an isolated island in 1957. Which of the following conclusions is best supported by the data?

• Every year, more individuals were born than died.

• A predator of this mammal was removed from the island in 1990.

• The population decreases were the result of low immigration rates.

• In the 1980s, the mammal’s population size stayed around its carrying capacity.

A small population colonized an isolated island. Over time, the size of the population increased to its carrying capacity, as represented in the graph below.

Which of the following conditions will most likely keep the population at its carrying capacity?

• a death rate of zero

• a death rate that is half the birth rate

• a death rate equal to the birth rate

• a death rate that is twice the birth rate

Tiger beetles chase small spiders, which they catch in their strong jaws and then eat. What is the ecological relationship between tiger beetles and spiders?

• Competition

• Mutualism

• Parasite-Host

• Predator-Prey

Which of the following expressions can be used to calculate the change in the size of a population?

• (births – deaths) + (immigrants – emigrants)

• (births + deaths) + (immigrants – emigrants)

• (births – deaths) + (immigrants + emigrants)

• (births + deaths) + (immigrants + emigrants)

Pompeii worms, Alvinella pompejana, live in tubes along hydrothermal vents on the sea floor. The worms are covered by a layer of bacteria. Scientists have discovered that the bacteria insulate the worms from the extreme heat of the vents, and the worms secrete mucus from glands on their backs to feed the bacteria.

Which of the following terms best applies to the relationship between the Pompeii worms and the bacteria?

• Competition

• Mutualism

• Parasitism

• Predation