Question 1

Mutualistic relationships can have an effect on the distribution and abundance of the species involved.

Accepted Answer

Mutualistic relationships can benefit both species involved, allowing for increased survival and reproduction. This can lead to changes in the distribution and abundance of the species, such as increased population size or range expansion.

Question 2

A species can participate in several symbiotic relationships simultaneously; for example,Scotch broom,an invasive shrub,competes with native vegetation for soil nutrients and maintains a mutualistic relationship with root bacteria.

Accepted Answer

It is possible for a species to participate in multiple symbiotic relationships at the same time. In the example given, Scotch broom competes with native vegetation for soil nutrients but also has a mutualistic relationship with root bacteria.

Question 3

If initially present,a mature community will reform immediately after a habitat disturbance.

Accepted Answer

A mature community will take time to reform after a habitat disturbance as the ecosystem needs time to recover and rebuild. The process of succession, where new species gradually replace the old ones, can take decades or even centuries.

Question 4

Humans negatively affect communities in a variety of ways; the community most common disrupted,usually by its complete removal,are ________.

Accepted Answer

The answer of Humans negatively affect communities in a variety...

Question 5

The general process by which species in a community are replaced over time is called ________.

Accepted Answer

The answer of The general process by which species in...

Question 6

Desertification,the transformation of dry grassland to a desert shrubland,can be natural or human caused; when humans are involved,the process is almost always associated with ________.

Accepted Answer

The answer of Desertification,the transformation of dry grassland to a...

Question 7

The inhabitants of an aquarium,despite its small size,could be considered a community.

Accepted Answer

A community is defined as a group of organisms living in a specific area and interacting with each other. In an aquarium, there are multiple species of fish, plants, and other organisms living in a confined space and interacting with each other. Therefore, they can be considered a community.

Question 8

Pollinators ingest seeds at the flowers they visit,carry those seeds in their digestive tracts,and later deposit them far from the plant that they fed on.

Accepted Answer

Pollinators typically transfer pollen, not seeds, between flowers. Seed dispersal is usually carried out by animals that eat the fruit containing seeds, not by pollinators.

Question 9

All natural communities consist of an equivalent number of species.

Accepted Answer

It is not necessary for all natural communities to have an equivalent number of species, as community composition can vary depending on factors such as environmental conditions, predation, and competition.

Question 10

During exploitation,consumer organisms never cause their prey to become extinct.

Accepted Answer

This statement is not entirely true. While some predator-prey relationships can be sustainable and balanced, others can lead to the extinction of the prey species if the predator over-exploits it. Additionally, human activities such as overfishing and hunting have led to the extinction or near-extinction of many species that were once heavily exploited by humans.

Question 11

Black oak trees are one of the earliest colonists after bare sand dunes are created.

Accepted Answer

Black oak trees are not typically early colonists of bare sand dunes; they usually require more developed soil and conditions to thrive. Early colonists are usually grasses and shrubs that stabilize the soil first.

Question 12

The interactions among organisms that reside in the same community or ecosystem are unlikely to have much effect on the physical aspects of those systems.

Accepted Answer

Interactions among organisms in a community or ecosystem can have significant effects on physical aspects such as nutrient cycling, energy flow, and even the physical structure of the ecosystem (e.g. the formation of coral reefs by coral).

Question 13

A community whose species are not replaced by other species is classified as a ________ community.

Accepted Answer

The answer of A community whose species are not replaced...

Question 14

Secondary succession is more likely to follow a disturbance to a mature community than primary succession because ________ typically remain intact.

Accepted Answer

The answer of Secondary succession is more likely to follow...

Question 15

The consumer in a predator-prey interaction can be a selective force in the evolution of the prey species.

Accepted Answer

The consumption of prey by predators can exert selection pressure on the prey population, favoring those individuals that are better adapted to avoid or escape predation. Over time, this can lead to the evolution of defensive traits such as camouflage, warning coloration, chemical defenses, or increased agility or speed. Thus, the consumer (predator) can be a selective force in shaping the traits and behaviors of prey species.

Question 16

Mistletoe participates in forest communities in many beneficial roles; its berries and leaves are food for herbivorous birds and insects,but to the trees that host it,mistletoe is strictly an undesirable ________.

Accepted Answer

The answer of Mistletoe participates in forest communities in many...

Question 17

Without pollinator mutualism,agricultural productivity could fall significantly.

Accepted Answer

Pollinator mutualism, such as the bees that pollinate crops, plays a crucial role in crop production. Without them, agricultural productivity could decline significantly, affecting food production and the economy. Therefore, the statement is true.

Question 18

Interactions among organisms are always mutually beneficial.

Accepted Answer

The answer of Interactions among organisms are always mutually beneficial....

Question 19

Succession has a major impact on the species makeup of a community at any given point in time.

Accepted Answer

Succession is the process by which the species composition of a community changes over time. As succession progresses, new species colonize the area and either replace or coexist with existing species. Therefore, succession has a major impact on the species makeup of a community at any given point in time.

Question 20

The terms mutualistic and symbiotic can be used interchangeably; any mutualistic relationship is an example of symbiosis,whereas any symbiotic relationship is also mutualistic.

Accepted Answer

Symbiosis includes mutualism, commensalism, and parasitism, but not all symbiotic relationships are mutualistic.

Quiz 23: Ecological Communities