<span>I think the pKa for acetic acid is about 4.74. Therefore Acetic
acid/acetate buffer will work best at 4.74 +/- 1 pH unit and so the pH 8 is far
removed from that. Hence it would not buffer at that pH at all.</span>
Answer:
Endocytosis is a form of active transport hence require enegry powered by ATP. The amoeba needs to change shape and engulf and envaginate the particle and then use vessicle transportation to get the materials into the cell. This requires that the cytoskeleton - composed of tubules and filaments - contracts and relax accordingly. This requires energy by ATPs just like the myosin and actin of muscle.
Phagocytosis, another form of endocytosis, is used by some cells such as immune cells to engulf foreign material and then destroy them by use of lysozymes. This is how phagocytes protect the body from invaders.
The KT boundary marks a mass extinction event. the KT boundary is the time between the Cretaceous and Tertiary periods. An asteroid hit the earth at the end of the Cretaceous and that caused the end of the Cretaceous period. Before the KT boundary, pollen from angiosperms and gymnosperms is high. After the meteor hits the earth, a mass extinction occurs and the amount of pollen from gymnosperms and angiosperms decreases dramatically, while the amount of spores from ferns increases. During the Cretaceous period there were many species of gymnosperms and angiosperms but they disappeared at the KT boundary, when the asteroid hit the earth.
Answer:
Autorhythmicity of the heart
Explanation:
It is the study of the characteristics features of the cardiac muscle cells with the ability to initiate action potential at certain level without connection to any external stimulus which the heart beats constantly and rhythmically. Cardiac muscle cells controls the rate of contraction of heartbeats.