Transportation in Human Beings || Life Processes - 6 || in Hindi for Class 10

In this Biology video in Hindi for Class 10 we explained blood circulation is carried out in human body. This topic is 'Transportation in Human Beings' from the chapter - 'Life Processes' From NCERT for class 10.

Circulatory System or Transportation System has four main components :
1) Heart
2) Blood vessels
3) Blood
4) Lymph

Heart :-

Human heart is situated between two lungs inside the rib cage. It pumps blood to the circulatory system. It has four chambers, two atria and two ventricles. From body blood comes to the heart through vena cava and enters right atrium. Through tricuspid valve, it then moves to the right ventricle. When this ventricle contracts, blood goes to the lungs through pulmonary artery. After being oxygenated blood comes to the heart again through pulmonary vein. Blood enters the left atrium and then it enters left ventricle through mitral valve. When this ventricle contracts, blood goes to the aorta, from where it reaches different parts of the body. Between right ventricle and pulmonary artery, there is a valve called pulmonary valve. Between left ventricle and aorta, there is a valve called aortic valve.

The separation of the right side and the left side of the 4-chambered heart is useful to keep oxygenated and deoxygenated blood from mixing, allowing a highly efficient supply of oxygen to the body. This is useful in animals that have high energy needs, such as birds and mammals, which constantly use energy to maintain their body temperature.

Animals like amphibians or many reptiles have three-chambered hearts. They tolerate some mixing of the oxygenated and de-oxygenated blood streams. Their body temperature depends on the temperature of the environment.

Fishes have only two chambers to their hearts. Blood is pumped to the gills, is oxygenated there, and passes directly to the rest of the body. Blood goes only once through the heart in the fish during one cycle of passage through the body.


Blood Vessels :-

Arteries are the vessels which carry blood away from the heart to various organs of the body. Since the blood emerges from the heart under high pressure, the arteries have thick, elastic walls.

Veins bring blood back to the heart. They do not need thick walls because the blood is no longer under pressure, instead they have valves that ensure that the blood flows only in one direction.

On reaching an organ or tissue, the artery divides into smaller vessels to bring the blood in contact with all the individual cells. The smallest vessels have walls which are one-cell thick and are called capillaries. The capillaries then join together to form veins that convey the blood away from the organ or tissue.


Blood :-

Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products and carbon dioxide away from those cells.

Blood has, mainly, two components, viz., Plasma and blood cells.

Plasma is made up of 55% of blood fluid and proteins, glucose, carbon dioxide, hormines, mineral ions etc. dissolved in it. Blood fluid is mainly water (92%).

Blood cells are, mainly, of three types, viz., R.B.C., W.B.C. and platelets.

R.B.C. :- Red blood cells or red blood corpuscles are the most common type of blood cell. These are the principal means of delivering oxygen to the body tissues. The cytoplasm of a red blood cell is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. 

W.B.C. :- White blood cells are the cells of the immune system that are involved in protecting the body against  infectious disease and foreign invaders. The different white blood cells are myeloid cells and lymphoid cells. Myeloid cells (myelocytes) include neutrophils, eosinophils, mast cells, basophils, and monocytes. Lymphoid cells (lymphocytes) include T cells, B cells and natural killer cells.

Platelets :- Platelets , also called thrombocytes are a component of blood whose function is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot.


Lymph :-

This is also called tissue fluid. Through the pores present in the walls of capillaries some amount of plasma, proteins and blood cells escape into intercellular spaces in the tissues to form the tissue fluid or lymph. It is similar to the plasma of blood but colourless and contains less protein. Lymph carries digested and absorbed fat from intestine and drains excess fluid from extra cellular space back into the blood.

👇👇👇👇👇👇 𝑷𝑳𝑨𝒀𝑳𝑰𝑺𝑻 👇👇👇👇👇👇

🔴 Click here to watch the whole playlist on Chapter 6 : 'Life Processes' for Class 10 :
   • Introduction to Life Processes || Lif...