Unit 5: Populations

Question 1

Differentiate between the two methods of estimating populations.

Answer 1

Quadrat Sampling: area is divided into equal portions, and certain portions are counted to find a general average
Mark/Release/Recapture:
total marked/total population = # marked recaptured/ # recaptured

Question 2

difference between crude and ecological density

Answer 2

crude: pop. density in terms of individuals in entire population
ecological: in terms of individuals per unit area that is actually used

Question 3

difference between interspecific and intraspecific competition

Answer 3

interspecific competition is competition between members of different species
intraspecific competition is competition between members of the same species

Question 4

mutualism

Answer 4

interaction where both sides benefit

Question 5

parasitism

Answer 5

interaction in which one species benefits and the other is harmed

Question 6

commensalism

Answer 6

interaction in which one species benefits and the other is unaffected

Question 7

resource partitioning

Answer 7

several species that live in the same place will use different resources or the same resources in different ways (e.g. zebras and gazelles both live in the same habitat, but zebras eat short grass and gazelles eat long grass)

Question 8

minimum viable population size

Answer 8

the smallest population size predicted to survive any environmental change

Question 9

herbivory

Answer 9

interaction between herbivorous animals and the plants they eat

Question 10

What might you conclude about a population of deer that consists of many pre-reproductive individuals?

Answer 10

The population has recently grown and will continue to grow (as the young deer become mature and have their own babies)

Question 11

exploitative competition

Answer 11

when two or more species exploit the same limiting resource