Demonstrate why keystone species play a large role in community despite the fact that they may be present in relatively small numbers
What will be an ideal response?
While the number of keystone species individuals may be low (e.g., sea stars, sea otters), particularly when they are top predators, their influence may be quite large with regard to population control and maintaining species diversity. The sea star, for example, is a top predator that prevents overpopulation and potential depletion of resources. Also, by keeping some of the more prolific competitors for other niches in check (e.g., mussels) sea stars allow less prolific competitors such as barnacles to survive. By preventing competitive exclusion of barnacles and other species, sea stars maintain species diversity in their communities.
You might also like to view...
Which of the following is true concerning a somatic cell mutation?
A. A small fraction of the gametes carry the mutation. B. Half of the gametes carry the mutation. C. All of the gametes carry the mutation. D. Only a small group of cells within the organism is affected by the mutation. E. All cells within the organism are affected by the mutation.
A researcher proposes that the relationship between a particular bacterial species that produces a fat-soluble vitamin is mutualistic with its insect host. Which of the following procedures would best test the researcher's hypothesis?
A. Design a method to isolate the bacteria from the insect, then mutate the bacteria in the region of DNA that controls vitamin production and compare growth of the mutant and wild-type bacteria on minimal media B. Extract the DNA from the bacteria and from the insect, then use reverse-transcriptase PCR and primers specific to the gene that controls vitamin synthesis to compare transcription of RNA in both organisms C. Determine which insecticide kills the insect without harming the bacterial host, then compare vitamin production by the bacteria from insects treated with the insecticide to those from untreated insects D. Determine which antibiotic kills the bacteria without harming the host, then administer this antibiotic to the insect and compare its growth with and without the vitamin
A woman whose mother is color blind and whose father has hemophilia A is pregnant with a boy. If the alleles for color blindness and hemophilia A are rare in the population, what is the probability that the baby will have normal vision and normal blood clotting?
In humans, the genes for red-green color blindness (R = normal, r = color blind) and hemophilia A (H = normal, h = hemophilia) are both X-linked and only 3 map units apart. A) 0 B) 0.03 C) 0.485 D) 0.47 E) 0.015
__________ and __________ are single-celled heterotrophs with a secreted shell. Fill in the blank(s) with the appropriate word(s)