Question

Write a short note on BLOOD.

Answer 1

$\huge\mathfrak{Blood}$

→ Transport of oxygen :- 

A small amount of oxygen is carried by plasma as it's aqueous solution from lungs to tissues for oxidation of blood.

→ Transport of Hormones :- 

The endocrine gland secrete their hormones directly into the blood, which carries them to their target organs.

→ Transport of Waste products :- 

Plasma carries nitrogenous waste namely; urea, uric acid, etc. from the liver and other tissues to the kidney for removal.

→ Regulation of water balance :- 

Plasma regulates the water balance of the body, as it supplies water to the tissues and receives the excess water formed in metabloic process.

→ Regulation of pH :- 

Plasma helps to regulate the pH of the body fluids.

→ Regulation of the body temperature :-

Plasma carried heat from the heat producing tissues such as muscles and glands to others.

→ Platelets :- 

Platelets play a role in blood clotting.

→ WBCs (white blood corpuscles) :-

The WBCs act as the soilders, scavengers and builder of the body.
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Answer 2

$\large\bold{Answer:-}$

Blood is a fluid connective tissue where the corpuscles or cells move in a blood plasma i.e., the liquid matrix or medium, or in other words, the fluid.

The blood cells are mentioned below :

1. Erythocytes or Red blood cells :-

• RBCs are red in colour, are biconcave rounded in shape and contains haemoglobin.

• Nucleus is absent including many other cell organelles that is why they are known as corpuscles.

• Their life span is of 120 days and they are only of one type.

• Their size is about 7.2 micrometer and their number is 4-6 million/mm³.

• They transport oxygen and sometimes carbon dioxide to some extent.

2. Leucocytes or White blood cells :-

• WBCs are colourless and their shape is basically rounded to amoeboid.

• Nucleus including other cell organelles are present in these cells.

• Their life span is generally shorter i.e., few hours to four days and they are of five types.

• Their size varies between 10-20 micrometer and their number is 6000-9000/mm³.

• They mainly function in immunity and defence.

3. Platelets :-

These are anucleated, minute, fragile fragments of giant bone narrow cells, called the megakaryocytes.

$\bf\underline{Occurrence:-}$

Blood occurs in the blood vessels namely known as the arteries, veins, and capillaries which connected altogether forms the circulatory system.

NOTE : The extensive branching network of the blood vessels enables the blood to reach each and every part of the body.

$\bf\underline{Functions\:of\:Blood:-}$

=> Blood transports nutrients and hormones as well as vitamins to several tissues and transports the excretory products from the tissues to liver and the kidney.

=> The RBCs carry oxygen (for the oxidation of the food particles and stuff) to the tissues.

=> The WBCs fight the diseases by either engulfing or destroying foreign bodies or producing antibodies and antitoxins that neutralizes the harmful effects of bacterias and germs.

=> The platelets disintegrate at the site of injury and helps in the clotting of blood.