• Written By Anu_V
  • Last Modified 17-04-2023

Human Heart – Definition, Diagram, Anatomy and Function

img-icon

Human Heart is the most important organ which pumps blood throughout the body via the cardiovascular system, supplying oxygen and nutrients to all other organs and removing waste and carbon dioxide from the body. Human heart functions throughout the life span of a human being and any abnormality in its functioning become a life-threatening medical issue.

Human heart is the most critical organ in human body. A human being can survive if there is an abnormality in the Liver, Kidney or Lungs for some time but if the human heart skips a heart bit it will be life-threatening. In this article, we will cover in detail about the Human heart, the structure of the human heart, functions of the human heart, important components of the cardiovascular system. You can check NCERT Solutions for Class 11 Biology Chapter 18 for a better understanding of the organ. We have provided detailed information on the human heart in this article. Read on to find out.

Human Heart: Definition

Human heart is basically a biological pump that circulates blood in the human body. The heart is the size of a human fist and is located between the lungs in the thoracic cavity, slightly towards the left of the sternum (breastbone). It forms the cardiovascular system together with blood vessels, veins and capillaries.

The blood is carried through arteries, arterioles and capillaries to the body whereas, blood is returned to the heart through venules and veins. The human heart is made of four chambers i.e., two upper left and right atria and two lower left and right ventricle. Any defect in the heart and its parts can lead to some of the heart ailments such as cardiac arrest, heart valve disease, pericardial effusion, myocarditis, myocardial infarction, coronary artery disease etc.

Human Heart with labelling
Source: NCERT Textbook

Anatomy of Human Heart

Human heart is situated in the thoracic cavity between two lungs slightly tilted towards the left. It is protected by a membrane known as pericardium. Human heart has four chambers namely, upper left and right atrium and lower left and right ventricles. The human heart is responsible for pumping blood through arteries and veins known as cardiovascular system. Human heart is made of cardiac muscle.

Structure of Heart

The human heart is made of muscles that can contract and relax rhythmically. This contraction and relaxation of heart in a rhythmic manner is known as heartbeat. Human heart is covered by the membrane known as pericardium enclosed in pericardial fluid. It protects the heart by serous fluid which lubricates the heart and prevents friction. The pericardium holds the heart in position. It has two layers i.e., visceral and parietal layers.

Chambers of Heart

To avoid the mix of blood rich in oxygen and carbon dioxide. Human heart has four chambers. There is a partition between the two chambers which does not allow the mix of blood.

  1. Right Atrium: These are called as blood receiving chambers. It receives blood from veins and pump it to right ventricle.
  2. Right Ventricle: It receives blood from the right atrium and pump it to the lungs.
  3. Left Atrium: It receives oxygenated blood from the lungs and pump it to the left ventricle.
  4. Left Ventricle: It pumps blood to the rest of the body.

There is a thin wall called interatrial septum that separates the right and left atria. Also, there is a thick wall called as inter ventricular septum that separates the left and right ventricles. The same side of the atria and ventricle are separated by fibrous tissue known as atrio-ventricular septum. There is an opening between the right atrium and right ventricle guarded by valves known as flaps or cusps. The tissue present in the upper right atrium is called as sinoatrial node( SAN). Whereas, the other tissue is seen in the left corner of the right atrium known as atrio-ventricular node (AVN).

Functions of a Human Heart

The functions of a human heart are as follows:

  1. It pumps oxygenated blood to the other parts of the body.
  2. It maintains blood pressure.
  3. It pumps hormones and vital substances to the body.
  4. It pumps de-oxygenated blood to the lungs which converts it into oxygenated blood.
Download NCERT Solutions for Class 11 Biology Chapter 18 PDF

Facts about Human Heart

Some of the facts about the human heart are as follows:

  1. The size of the human heart is similar to size of closed fist.
  2. The weight of the heart is around 280-340 grams in men and 230-280 gram in female.
  3. The heart beat in human is about 1,00,000 times per day.
  4. For adult, heart beat is 60-80 times per minute.
  5. The newborns heart beats are much faster then adults which is around 70-190 per minute.

FAQs Regarding Human Heart

The frequently asked questions on human heart are given below:

Q. What are the interesting facts about the human heart?
A. The size of the human heart is similar to the size of a closed fist and the weight of the heart is around 280-340 grams in men and 230-280 grams in females.
Q. How many chambers are there in a human heart?
A. There are four chambers in a human heart i.e., upper left and right atria and lower left and right ventricle.
Q. What is the function of a human heart?
A.
Human heart pumps blood throughout the body via cardiovascular system, supplying oxygen and nutrients to all other organs and removing waste and carbon dioxide from the body.
Q. Where is a human heart situated?
A. Human heart is an organ located in the thoracic cavity between two lungs slightly tilted towards the left.

We have now provided you with detailed information on the human heart. We hope this detailed article helps you. If you have any questions, feel to ask in the comment section below. We will get back to you at the earliest.

Practice Human Heart Questions with Hints & Solutions