Question

Short / Long type answer type questions.
Describe the external and internal structure of human heart.

Answer 1

• The external structure of heart :
  

1. The heart is located in the centre of the chest cavity slightly tilted towards the left.

2. The human heart has a mass of between 250 and 350 grams and is about the size of a fist.

3. It is a hollow muscular organ made up of cardiac muscle fibers.

4. It is enclosed in a double-walled sac called the pericardium.

• The internal structure of heart :

1. The human heart has four chambers, two upper atria and two lower ventricles

2. Pulmonary artery and aorta leave the heart while pulmonary vein and vena cava enter the heart.

3. Four different valves control the movement of blood in and out of the heart ; Bicuspid, Tricuspid and Semilunar valves.

4. Coronary artery supply the musculature of heart.