Question

Explain with reasons.
a. Human blood is red colured.
b. Upward and downward movement of diaphragm occurs consecutively.
c. Blood donation is considered to be superior of all donations.
d. person with 'O' blood group is considered as 'universal donor'
e. Food must have limited amount of salts.

Answer 1

a. Human blood is red in colour due to the presence of the respiratory pigment haemoglobin. Haemoglobin is a pigment which is red in colour and thus imparts red colour to the blood.

b. Diaphragm is a muscular partition which is present between the thoracic cavity and abdominal cavity. During the process of breathing, the upward and downward movement of diaphragm occurs simultaneuosly. When we inhale, the ribs rise up while the diaphragm lowers down simulatenously causing a decrease in pressure on lungs. This results in the moving of air into lungs through nose. As the ribs return to their original position, diaphragm rises up leading to the increase in pressure inside the lungs. This results in moving of the air outside the nose.

c. Blood donation is considered superior of all donations because it can save someome's life. Most of the lives are lost due to blood loss during surgeries, accidents or cases where regular blood transfusion is required. These lives can be saved, if adequate amount of blood is available.

d. Person with 'O' blood group is considered as 'universal donor' because such an indivisual can donate blood to a person having any other blood group.

e. Food must have limited amount of salts as we require limited amounts of these in our body. Excessive salts in food can lead to accumulation of water in different parts of the body such as arms, legs etc. and lead to edema. Too much salt leads to increase in the blood pressure as well.