Biology Questions

The nucleotides that are present in DNA molecule are 4. They are Thymine (T), Guanine (G), Adenine (A) and Cytosine (C).

Here in this Adenine pairs with Thymine (A - T) and Cytosine pairs with Guanine (C - G).

Goitre is characterized by the swelling of the neck region. This is due to the enlargement of the thyroid gland which secretes hormone thyroxine. Thyroxine has iodine as an integral part of it. If there is not sufficient iodine in one's  diet, the thyroid gland swells up.

The prostate gland is a walnut-sized structure that is located below the urinary bladder in front of the rectum. The prostate gland contributes additional fluid to the ejaculate. Prostate fluids also help to nourish the sperm. The urethra, which carries the ejaculate to be expelled during orgasm, runs through the center of the prostate gland.

Uracil is not found in DNA but found in RNA.

Salivary glands of man are 3 pairs = 6. They are one pair of parotid glands, one pair of sub-maxillary or sub-mandibular glands and one pair of sub-lingual glands.

Saliva is produced by the salivary gland which helps in food digestion.

Option A) contains fluoride to harden the tooth enamel is not the function of saliva.