Reproducing plant and animals Which have desirable traits is called

Which of the following statements about protists are true? a.they are typically found in moist environments. b.they are all unicellular. c.they have a nucleus. d.they are all multicellular.

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins

Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population.b) the separated population is small, and genetic drift occurs.c) the isolated population is exposed to different selection pressures than the ancestral population.d) different mutations begin to distinguish the gene pools of the separated populations.e) gene flow between the two populations is extensive.