1.) Which of the following factors would affect population distribution but not size in a given country?
A) individuals moving from this country to another country
B) an increased birth rate
C) individuals moving from one region of the country to another region of the same country
D) an increased death rate

2.) A researcher is studying a particular population. He notices that the carrying capacity for this species in this ecosystem has decreased. What could have caused this change?
A) The resources available for the population have increased.
B) The population is breeding too quickly and producing too many offspring.
C) The resources available for the population have decreased.
D) The population is breeding too slowly and not producing enough offspring.

3.) Which of the following would be an appropriate measure of population density?
A) the number of African elephants (Loxodonta africana)
B) the number of African elephants (Loxodonta africana) and the grasses on which the elephant feeds per square mile
C) the number of African elephants (Loxodonta africana) and humans per square mile
D) the number of African elephants (Loxodonta africana) per square mile

4) Diseases can spread rapidly in cities. If a disease kills many people in a city but fewer in a rural area, this is an example of
A) exponential population growth.
B) density-independent factors.
C) logistical population growth.
D) density-dependent factors.

1. C

2. C

3. D

4. D

Explanation:

1.

Population distribution is how the individuals of the population are spatially distributed across the habitat. For example, It could be uniform distribution where spaces between individuals are more or less equal on average or clustered form of distribution where they are many individual clustered at different points.  

2.

Carrying capacity is the number of individuals of a population that a habit can sustain indefinitely because they allow for the resource to replenish. If the population exceeds the carrying capacity, it becomes unsustainable and the population will likely experience in ‘burst’ in population size. A decrease in the number of resources therefore also means a decrease in the carrying capacity.

3.

Population is related to one species while a community is to many species in a habitat. Therefore population density is the number of individuals of a species, occupying a habitat, per square area. The higher this figure the higher the population density.

4.

Density-dependent factors mean that these factors are influenced by the density of the population. In this case rate of infection of the disease is dependent on the density of the population The higher the density the higher the infectivity and vice versa.

Answer No 1) The correct option is C) individuals moving from one region of the country to another region of the same country

Explanation:

Population distribution can be described as the population of organisms in a certain area.

Individuals moving from one plane to another will cause the population distribution of that area to change. However, as the migration will occur inside the same country, the size of the population will remain the same. Hence, the correct option is C.

Answer No 2)

The correct option is C) The resources available for the population have decreased.

Explanation:

Carrying capacity can be described as the number of organisms in a particular population that an area can hold. The more the resources available in an ecosystem, the more will be the carrying capacity. The lesser the number of resources in an area, the lesser will the carrying capacity of that area. Hence, the correct option is C.

Answer No 3) The correct option is D) the number of African elephants (Loxodonta africana) per square mile

Explanation:

Population density can easily be described as measurement of population is a given area. Population density is calculated by dividing a particular population with the area. As option D, represents the dividing of the number of African elephants with the area hence it is the correct option.

Answer No 4) The correct option is B) density-independent factors.

Density independent factors can be described as the factors which are not dependent on the population of an area. As the scenario in the question reflects that a disease is occurring more in a city irrespective of the population density, hence it will be a density independent factor.

b a mature ovary of a plant.