Which of the following is an example of a monosaccharide? MCQ with Answer and Explanation

Explanation:
Colostrum, the first milk produced by the mother, is rich in IgA antibodies, providing natural passive immunity to the newborn. Allergies (hypersensitivities) occur when the immune system overreacts to harmless environmental antigens (allergens). Autoimmune diseases arise when the immune system loses tolerance and mistakenly attacks the body's own healthy cells and tissues. All statements are correct.

Explanation:
Retroviruses (e.g., HIV) possess two copies of single-stranded RNA and the enzyme reverse transcriptase, which transcribes the RNA into DNA upon infection. This DNA integrates into the host genome. Other viruses may have dsDNA, ssDNA, or dsRNA, but the defining feature of retroviruses is the RNA genome and reverse transcription.

Explanation:
Cataract is clouding of the crystalline lens leading to decreased vision, commonly age-related. Glaucoma is optic nerve damage often due to increased intraocular pressure. Myopia is nearsightedness, hypermetropia is farsightedness. Cataract surgery replaces the lens with an artificial one.