Explain the role of nutritional systems in contributing to the maintenance of homeostasis in organisms.

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

Why did mendel use pea plants in his experiments? a. they have no alleles. b. they are haploid organisms. c. they reproduce quickly. d. they are all male.

An animal cell (left) and a plant cell (right) are shown.which organelle, labeled x in the diagram, is found in both plant and animal cells?