Which of the following statements are correct about Sino-atrial node
A) It is responsible for initiating and maintaining the rhythmic contractile activity of the heart
B) It is auto-excitable and generates 70 - 75 action potentials per minute
C) It sets the pace of the activities of the heart and is called pacemaker

Which is responsible for initiating and maintining the rhythmic contractile activity of the heart ?

Assertion : The sino-atrial node (SAN) is called the pacemaker. Reason : SAN is responsible for initiating and maintaining the rhythmic contractile activity of the heart.

Answere the following name the major site where RBCs are formed which part of heart is responsible fpr initating and maintaining its rhythmic activity ?

a. SAN generates as action potential which stimulates atrial systole. b. ECG is an electrical representation of the graphical activity of the heart during a cardiac cycle. c. The cardiac output of a normal man will be much lesser than an athlete. d. The wall of right ventricle is much thicker than the left ventricle e. In pisces the two separate circulatory pathways are present, hence they have double circulation. f. The clsoed circulatory pattern is considered to be more advantageous than open circulatory pattern. g. Glucose is absorbed by simple diffusion through lymph in lacteales present in the intestinal villi. h. The SAN can generate the maximum number of action potential i.e. 140-150 mi n^(-1) in neonates, and is responsible for initiation and maintenance of the rhythmic contractile activity of the heart. i. Angina can occur in any age but more common among the neonates and infants. j. heart failure is sometimes called congestive heart failure because congestion of the blood vessels is one of the main symptoms of this disease.

Which of the following statement is correct. (A) The electrical potential difference across the polarised plasma membrane is called as action potential in resting stage. (B) Na^+ ion is responsible for generating an action potential. (C) The impulse is action potential

Assertion : Sino-atrial node (SAN) is called the pacemaker Reason : SAN generates the maximum number of action potentials and is responsible for intiating and maintaining the rhythmic contractions of the heart.

Which of the following statements about conducting system of the heart is INCORRECT ? I. Mass of nodal tissue seen in the lower-left corner of the right atrium is the sinoatrial node. II. The nodal musculature can generate action potentials only in response to external stimuli . III. The number of action potential that could be generated in a minute varies at different parts of the nodal system . IV. The SAN can generate the maximum number of action potential , i.e., 80-85 min^(-1)

Read the following statements and choose the correct option Statement 1 : Atria receive blood from all parts of the body which subsequenctly flows to ventricles Statement 2 : Action potential generated at sino-atrial node passes from atria to ventricles.

Read the following statements and choose the correct option Statement 1 : Atria receive blood from all parts of the body which subsequently flows to ventricles. Statement 2 : Action potential generated at sino-atrial node passes from atria to ventricles.