Several species of sea urchins may inhabit the same tide pool and their reproductive periods overlap. Although they practice external fertilization, they seldom interbreed because eggs produce chemicals that are only attractive to sperm of their own species. This is an example of a _________ barrier that _______________.
A. prezygotic; causes geographic isolation
B. prezygotic; causes temporal isolation
C. prezygotic; prevents gamete fusion
D. postzygotic; prevents zygote fusion
E. postzygotic; causes hybrid infertility
C. prezygotic; prevents gamete fusion
You might also like to view...
How does sickle cell disease cause death?
a. The malformed red blood cells cannot transport oxygen. b. The malformed red blood cells can block capillaries. c. The malformed blood cells have a higher affinity for CO2 than for oxygen. d. The mutant hemoglobin polypeptide cannot bind O2 due to a change in three amino acids. e. More cells assume the sickle shape as oxygen concentration in the tissues increases.
Most available carbon is present as ____
a. CO2 b. CaCO3 c. C d. HCO3¯ e. N2
Four of the five statements listed below are portions
of a well-known theory. Select the exception. a. Cells are the structural and functional components of living things. b. Cells arise from preexisting cells. c. All organisms are composed of cells. d. Cells are the basic living unit of organization of living things. e. All cells have a nucleus.
Which type of cell division occurs during growth and repair of tissues?