Answer:
The bottom one shows how the circulatory system of a fish functions.
B. mitochondria and nucleus
Perhaps the world's most famous early human ancestor, the 3.2-million-year-old ape "Lucy" was the first Australopithecus afarensis skeleton ever found, though her remains are only about 40 percent complete (photo of Lucy's bones). Discovered in 1974 by paleontologist Donald C.
Answer:
All of the above is the answer.
Answer:
provide a means of rapidly transmitting the action potential from the surface into the central portions of the muscle fiber
Explanation:
T-tubules or Transverse tubules are the tube-like structures present in the muscle fibers.
The T tubules are formed by the modification in the plasma membrane of the cell and therefore arise from the surface of the muscle cell. The T tubules then pass through the muscle and enter the inner core of the muscle that is near to the sarcoplasmic reticulum.
The main function of the T tubules is to carry forward the action potential from the synaptic junction to the muscle where it triggers the release of the calcium from the muscle.
Thus, the selected option is correct.
