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.
Answer:
The populations of different artic animals would start to decrease because of the lack of land and food.
Answer:
There are four bases in DNA, and they combine in a specific way. Adenine pairs with thymine, and guanine pairs with cytosine.
Explanation:
Answer: A variety of substances will dissolve oil, including gasoline and carbon tetrachloride -- both of which have non-polar molecules. Acetone is a special class of solvent called “dipolar aprotic” that, depending on the circumstances, can act as a weak acid or base; it dissolves oil and mixes with water as well.
Explanation: