Bio02A (General Ecology Lec)
True or False: write T if the statement is true and F if it is false (right minus wrong)
_____ 1. Extinction is the process of eliminating or reducing a conditioned response by not reinforcing
_____ 2. Removal of the keystone species can have beneficial effect in the ecosystem
_____3. Ecological extinction is a series of secondary extinctions that is triggered by the primary
extinction of a key species in an ecosystem.
______4. Declined number of sea otter results in decline numbers of sea urchins
______5. Population get smaller it becomes more vulnerable to demographic catastrophes. Causing
reproductive rates to decline and population numbers to decline even further.Eventually,
population disappears entirely.
______6. Genetically variable individuals tend not to have a copy of deleterious dominant alleles
______7. When a population become extremely large, extinction will follow
______8. Secondary extinctions are likely to occur when the threatened species areindependent on a
few specific food sources
______9. Secondary extinctions are likely to occur when the threatened species are forced to coexist
with an invasive species that is introduced to the ecosystem
_______10. Increased number of flying foxes leads to decreased number of pollinating plants.
Essay: Put your answers at the backpage.
a. Briefly discuss the fate of kelp forest ecosystem if sea otter continue to decline in numbers (5pts)
b. In your understanding about keystone species, cite one ecosystem wherein keystone species played a
vital role in it by giving emphasis on its effect on the ecosystem. (5pts)