The answer is C. large changes in allele frequencies can occur in a short time.
Genetic drift is a change in the frequency of alleles in a population as a result of random sampling of organisms and it decreases genetic variation of the population. In specific circumstances, large and rapid changes in allele frequencies can occur in a short time. The smaller the population, the more susceptible it is to genetic drift.
Answer:
If the mitral valve doesn't close properly, systemic circulation will be affected.
Explanation:
The correct answer is option D, difficulty of redesigning workable ecosystems
Reason -
The area that was redesigned into an ecosystem actually failed to attract the endangered species of clapper rails in California because of the following two reasons –
a) Failed attempt of restoration of Cord grass ( a tree which is a dominant tree in the nesting habitat of clapper rail) . Even if few such trees were there they could not grow to their full height and thus were incapable of providing adequate nesting cover
b) Due to the lack of predatory insect, some herbivore insect in the ecosystem attacked the green grasses thereby making the nesting inadequate.
Answer:
In order for a fracture to heal, the bones must be held in the correct position and protected. Soon after a fracture occurs, the body acts to protect the injured area, and forms a protective blood clot and callus around the fracture. New "threads" of bone cells start to grow on both sides of the fracture line.
Explanation:
The answer is c because curies release energy from the radiation