14.6.3 Interspecific Associations: Symbiosis

Question 1

Interspecific Associations: Symbiosis

Answer 1

• Four types of interspecific interaction:
 · predation
 · competitive exclusion
 · mutualism
 · commensalism
• Three examples of symbiosis:
 · parasitism
 · mutualism
 · commensalism
• Because actual interspecific interactions in nature are complex, they are often difficult to categorize.

Question 2

interspecific interavtion

Answer 2

• The table on the far left categorizes two different types of interspecific interactions.
• Review: In predation, an organism (usually an animal)
  obtains most of its food by eating other animals. - Predation is classified as a +/- interactionbecause the predator benefits and the prey is harmed (eaten).
• In parasitism, a form of predation, one organism (the
  parasite) feeds on another (the host) without killing it
  immediately (if ever). Parasites are generally specific to particular host species. Acting as a parasite, the female mosquito sucks blood to nourish eggs in her abdomen.

Question 3

mutualism

Answer 3

• an association between two or more species
  that benefits the organisms involved.
• Invertebrate animals called polyps live symbiotically with zooxanthelae. The skeletons of the polyp form what is known as “coral.” If the water temperature is high (global warming), the polyp will release the zooxanthelae, thereby disturbing the vitality of the coral reef ecosystem.

Question 4

commensalism

Answer 4

• one species benefits and the other is
  apparently not affected. Whether or not one of the species is completely unaffected is still debated.
• While the herd of cattle grazes, they inadvertently flush insects from the vegetation, and the cattle egrets eat these insects.
• Question: Is this truly a commensalistic relationship?
  Community ecology seeks information about these and other interspecific interactions.

Question 5

Which of the following statements about parasites is not true?

Answer 5

• Parasitism can be described as a +/0 interspecific interaction.

Question 6

Which of the following relationships is not mutualistic?

Answer 6

• cattle egret and cattle

Question 7

True or false?
The categories predation, parasitism, mutualism and commensalism allow us to classify every type of interspecific association known

Answer 7

• false

Question 8

To what does “coral bleaching” refer?

Answer 8

• when symbiotic microalgae are expelled from the coral polyp

Question 9

In the disease malaria, the mosquito acts as a __________ for Plasmodium sp., which it carries in its body cavity and injects it into humans.

Answer 9

• vector

Question 10

Which of the following interspecific interaction classifications is most often used to describe predation?

Answer 10

• +/−