Question

Describe the structure of heart.write a short note
​

Answer 1

Heart is located in the thoracic cavity , in between the two lungs slightly tilted to the left.

It is derived from mesoderm and has the size of clenched fist,

Heart is protected by a double walled membranous bag called pericardium.

Pericardium consists of 2 layers ,outer parietal pericardium and an inner visceral pericardium attached to the heart.A space called pericardial cavity is present between two layers which is filled with fluid called pericardial fluid .

Pericardium protects the heart from shocks and mechanical injuries.

Our heart is divided into 4 chambers two relatively small chambers called atrium and two larger lower chambers called ventricles

The right and left atrium is separated by THIN muscular Interatrial  septum

Answer 2

$\huge\underline{\underline{\textbf{Human\:Heart\::}}}$


→ Heart is a hollow, muscular organ present in between two lungs in tye thoraric cavity. It's size is about one's fist. It is 12 cm long and 6 cm wide.

→ It's weight in male is 300 gm and 250 gm in female. It's is reddish brown in colour.

→ It's upper broad part is known as base and lower part is known as Apex.

→ It's is protected by a double members called pericardium, comprising inner visceral pericardium and outer parietal pericardium.

→ Between these layers there is a fluid called pericardium fluid. This fluid provides moisture to the heart and reduce the friction between heart wall and surrounding tissue.

→ A human heart is four chambered. Two upper; smaller chambers called atria and the lower; longer chambers called ventricle.

→ The atrium and ventricle of the same side are separated by atrio-ventricular septum.

→ Atrial septum separates the left and right atria. Inter ventricular septum separates the left and right ventricles.

→ The opening between right atrium and ventricle is guarded by a valve called Tricuspid valve.

→ And the opening between left atrium and ventricle is guarded by a Bicuspid valve.

→ Valves prevent the backward flow of blood and allow the blood to flow in one direction only.