TOPIC - STRUCTURE & FUNCTION OF HEART(SCIENCE)

  STRUCTURE & FUNCTION OF HEART

The human heart is a muscular organ, about the size of a fist, that acts as a pump to circulate blood throughout the body. It's divided into four chambers: two atria (upper) and two ventricles (lower). These chambers are separated by valves that ensure one-way blood flow. The heart's main function is to pump oxygenated blood to the body and deoxygenated blood to the lungs, while also maintaining blood pressure and distributing hormones. 

Structure:

Chambers:

The heart has four chambers: the right atrium and right ventricle, and the left atrium and left ventricle. 

Valves:

Four valves – tricuspid, pulmonary, mitral (bicuspid), and aortic – ensure blood flows in the correct direction through the heart. 

Layers:

The heart wall has three layers: the epicardium (outer), myocardium (middle, muscular), and endocardium (inner). 

Major Blood Vessels:

The aorta, vena cava, pulmonary arteries, and pulmonary veins connect the heart to the lungs and the rest of the body. 

Septum:

The septum divides the heart into right and left sides, preventing the mixing of oxygenated and deoxygenated blood. 

Function:

1. Pumping blood:

The heart pumps oxygen-rich blood from the lungs to the rest of the body (systemic circulation) and pumps oxygen-poor blood from the body to the lungs (pulmonary circulation). 

2. Receiving blood:

The atria receive blood from the body (right atrium) and the lungs (left atrium). 

3. Maintaining blood pressure:

The heart's pumping action creates the pressure needed to circulate blood throughout the body. 

4. Distributing hormones:

The heart plays a role in distributing hormones produced by other organs. 

5. Circulation:

The heart, along with blood vessels, forms the circulatory system, which delivers oxygen and nutrients to cells and removes waste products.