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 amount of people per square mile or kilometer of land; also called arithmetic density.
I am pretty sure that if muscle cells failed to function properly the thing that would happen is being revealed by the first option : A. The muscles will not work. I choose this one because as you know muscles are made of muscle tissue and if cells fail it won't functionate at all.
Answer:
List three ways of reducing friction. 1.Polishing the rough surface. 2.Providing all bearings or wheels between the moving parts of a machine or vehicles reduce friction and 3.allow smooth movement as rolling friction is less than sliding friction.
The organelle responsible for keeping the cell clean is the cell membrane.
