Ch.14-Interactions among organisms: Mutulism, Commensalism, Amensalism

Question 0

Trophic mutualism

Answer 0

a mutualist receives energy or nutrients form its partner

Question 1

Mutualism

Answer 1

a mutually beneficial interactions between individuals of two species

Question 2

Habitat mutualism

Answer 2

a mutualist receives shelter from its partner

Question 3

Service mutualism

Answer 3

mutualist receives an ecological service from its partner (pollination, dispersal, defense against predators, etc. )

Question 4

Facultative mutualism

Answer 4

the species benefit from their partners,but can live without them

Question 5

Obligate mutualism

Answer 5

the species are so dependent on each other that they cannot survive apart

Question 6

Mutualism example: ants in acacia

Answer 6

ants receive: protection and protein

tree: protection from other insects

Question 7

Farming

Answer 7

Generally considered a mutualism because the farmed organisms usually increase in abundance
Ex: leaf cutter ants farming fungi -> produces protein (food for ants)

Question 8

Amensalism

Answer 8

a relationship where on species suffers while the other is unaffected

• not common
  ex: as wild pigs forage, they often disturb the soil and tear up plants but they are not effected

Question 9

Commensalism

Answer 9

an interaction between individuals where on benefits the other, but is not harmed
Ex: Kelp forest (provides habitat for many juvenile fish )
Ex: pearlfish live in the cloaca of sea cucumber (sea cucumber provides protection and some nutrients -> could become exploitation

Question 10

Difficulties in classifying interactions

Answer 10

-Mutualist for one type of tree my be parasite on another type
-Human gut bacteria:
~some “bad bacteria” produce toxins (over time, can lead to cancer)
-Cows and humans:
~the global population of cows is much higher than it would be without humans