Question

Q1. Under what condition, pacemaker is implanted and why?

a. When natural pacemaker ( SA node) is unable to work efficiently,
b. When (AV node) is unable to work efficiently, then to maintain a stable heart rate.
c. When cardiac muscle is unable to work efficiently,
d. When hpulse rate is abnormal.

Q2. How many chambers are present in the heart of a frog?

(a) 2 chambers
(b) 3 chambers
(c) 4 chambers
(d) 5 chambers

Q3. Which of the following has thickest wall?

(a) Right ventricle
(b) Left ventricle
(c) Right atrium
(d) Left atrium​

Answer 1

Answer:

1. Answer is option a

2. Correct option is b - 3 chambers

3. Correct option is b - Left ventricle

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