Question

blood red kyo hota hai kiske karan

Answer 1

Because of haemoglobin present in blood..

Answer 2

Answer...✍
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$\textbf{Haemoglobin}$ present in red blood cell. $\textbf{It gave red colour to blood.}$ It carry oxygen from our lungs to rest of the body. It helps in absorption of minerals and other nutrients. It also plays a important role in maintaining the shape of the red blood cells.

→ Whenever it react with oxygen it is known as oxyhaemoglobin amd when it react with carbon dioxide it is known as carboxyhaemoglobin. Addition of oxygen and carbon dioxide releases a gas named nitric gas. Nitric gas helps in regulation of blood pressure. 

→ Haemoglobin is made up of 4 molecules of proteins that are joined together. Each haemoglobin carries 4 molecules of oxygen and it carries carbon dioxide in the form of bicarbonate. 

→ Normal concentration of Haemoglobin in blood :- 

* In female = 11 - 15 g/100 ml of blood. 

* And in male = 12 - 17 g/100 ml of blood.

→ Anemia is a disease which occurs due to deficiency of haemoglobin in our body.

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