Deficiency of vitamin B₁ causes beriberi, iron deficiency causes anaemia, haemophilia is a genetic disorder, and phosphorus deficiency causes bone fragility in humans.

Butter is a rich source of fat, and sugars are carbohydrates. A fat molecule has more carbon-hydrogen bonds than a sugar molecule. Thus, a large amount of energy can be obtained by the breakdown of fat molecules as compare to the same amount of carbohydrates.

Lymph is the fluid that circulates throughout the lymphatic system. Approximately half of the lymph formed in the body is formed in the liver.

Vitamin K is necessary for the synthesis of prothrombin in the liver for normal clotting of blood. 

Vitamin C is a water soluble vitamin and is present in the largest amount in the body in the adrenal cortex. It is essential for healthy gums, bones  teeth, and formation of erythrocytes and antibodies.

Vitamin D is also known as calciferol. It is required for the normal absorption and deposition of calcium and phosphate. 

The permanent teeth of a man includes 8 incisors, 4 canines, 8 premolars and 12 molars. Thus, there are 4, 2, 4, 6 incisors, canines, premolars and molars respectively in each jaw of man.

Vitamin E or Tocopherol is an excellent anti oxidant. It helps to keep the skin healthy and decreases the fragility of erythrocytes. 

During prolonged starvation, the body derives its nutrition from liver and adipose tissue where the nutrients are stored to be used during certain emergency conditions.

A fat molecule has more carbon-hydrogen bonds than a sugar molecule. Thus, a large amount of energy can be obtained by the breakdown of fat molecules as compare to the same amount of carbohydrates. 

Citrus fruits, oranges, etc. are rich sources of vitamin C. So, the patient suffering from its deficiency should be advised to take the citrus fruits.

Saliva of humans is slightly acidic so as to inhibit the action of harmful microbes. Its pH range is 6.7 - 6.9.

Vitamin C is essential for healthy gums, bones and teeth and formation of erythrocytes and antibodies. It helps to maintain the walls of the blood capillaries. 

The largest gland of the human body is the liver. It is almost as large as the stomach. Adrenal glands are small pyramids present just above the kidneys while thyroid gland is also a small bow-shaped gland accommodated behind the throat. Salivary glands are too small and are present in the mouth. Thus, (1), (3) and (4) are all small sized glands, and only option (2) is correct.

The gall bladder is attached with liver and it receives bile from the liver when there is no food in the duodenum for emulsification. Thus, gall bladder stores the bile. Since gall bladder is much smaller than liver, the bile has to be concentrated for storage. Hence, (3) is correct. It should be noted that gall bladder can't produce bile.