Question

Question 15 1 pts What is role of the “funny current" through the HCN channel? It allows Ca2+ influx, which activates RyR channels. It's responsible for Phase 2 of the cardiac myocyte action potential It establishes maximum diastolic potential in cardiac myocytes O In pacemakers, it starts the slow depolarization of phase 4

Answer 1

15.Answer- In pacemaker,it starts the slow depolarization of phase 4

The HCN channels refer to the hyperpolarization activated cyclic nucleotide gated channels which allow the pacemaker electric current (also called as funny current) to pass through the heart. The funny current is involved in the pacemaker activities and the diastolic depolarization but not interferes with the phases of action potential.The funny current causes the permeabilization of sodium and potassium ions, generating the inward current and slow diastolic depolarization at phase .The phase 3 refers to the hyperpolarization which has maximum diastolic potential.

14.Arteriole

The arterioles are the fine blood vessels with small diameter which branches out from arteries and the arterioles branches to form capillaries.It has greater resistance because this is the site where the comparatively large diameter arteries transit dramatically into arterioles and slows down the flow.