Without crossing over:

A. cells could not complete meiosis.
B. meiosis could not produce haploid gametes.
C. only a small number of unique gametes could be produced by a single individual.
D. genetic recombination could not occur.

Which of the following is an example of a non-falsifiable hypothesis? a. there is a teacup orbiting the milky way galaxy. b. there is no life on mars. c. the human species started in africa. d. humans cannot live without the amino acid methionine

Rank the three variables in terms of how strongly they affect the "species" composition of the bacterial communities. place the variable with the weakest effect on the left and the variable with the strongest effect on the right.

Match the following terms describing electrical events with the correct phases of the cardiac cycle. the ventricular muscle cells depolarize at the start of this phase. during this phase, na+ entry through the funny channels causes the pacemaker potential of sa nodal cells to gradually become less negative until it reaches threshold. the ventricular muscle cells repolarize right before this phase. the cytosolic concentration of calcium in the contractile cells of the ventricle is highest during this phase. a. isovolumetric relaxation b. ventricular ejection c. isovolumetric contraction d. ventricular filling