Which of the following statements is true with regard to this animation? sodium ions are transported down their concentration gradient. both sodium and potassium ions are transported against their concentration gradients. the cell is not expending energy. the cell does not expend atp. potassium ions are transported down their concentration gradient

Assume that a student is given two different models of bacteria, with one model consisting of big bacteria and the other consisting of small bacteria. how can the student demonstate the theory of endosymbiosis using the models

Amylase is an enzyme found in the human digestive system. why do you think it was important to keep the enzyme temperature about 37 degrees celsius (98.6 degrees f)? describe what might happened the temperature decreased by 10 degrees celsius.

Humans are believed to have evolved in coastal regions in east africa. the region had an abundant supply of fish for early humanoids to eat. when scientists analyze the fads gene they see an interesting pattern. people whose families have lived in this area of east africa for generation show a high level of diversity in alleles for the fads gene. conversely, people whose families had migrated inland a moderate distance from sources of fish showed a much lower diversity for fads gene alleles. additionally, the fads alleles found in people whose family has lived inland for generation are almost all gene alleles which produce fads proteins with a high level of function and activity. how do anthropologists explain this?