Answer:
Stem cells has a great contribution in order to maintaining homeostasis in the body because stem cells are produced rapidly and sent to the sites of the body where cells are old or get damaged maintain stability in the body.
Explanation:
Stem cells are specially type of cells which has the ability to change their structure according to the cell needed by the body. If brain cells are damaged, stem cells change their shape according to the brain cells and perform their functions by replacing the damage cells.
B. Hypothalamus and pituitary gland
Answer:
The correct answer will be option-C
Explanation:
The rhythm of the heartbeat is controlled by the pacemaker of the heart called the sino-atrial node.
The SA node generates action potentials which trigger the contraction and relaxation of the atrium and ventricles. The membrane potential generation initiates by the depolarization of the cell membrane when the L type of Ca⁺² ions opens up and calcium ions enter the cell.
This depolarizes the cell until the potential threshold is reached which lies between the -40 and -30 mV.
Thus, Option-C is the correct answer.
