The largest gland in the human body is the: MCQ with Answer and Explanation

Explanation:
Codominance occurs when both alleles in a heterozygote are fully and equally expressed. In the ABO blood group system, the IA and IB alleles are codominant. An individual with the genotype IAIB will have both A and B antigens on the surface of their red blood cells, resulting in the AB blood type. It also involves multiple alleles (IA, IB, i).

Explanation:
Pernicious anemia is a megaloblastic anemia resulting from vitamin B₁₂ (cobalamin) deficiency, often due to lack of intrinsic factor (produced by stomach parietal cells) needed for its absorption. It is characterized by large, immature red blood cells and neurological symptoms. Iron deficiency causes microcytic anemia. Sickle cell is genetic, aplastic is bone marrow failure.

Explanation:
Bacterial infections (like tuberculosis, pneumonia) are effectively treated with antibiotics, which target specific bacterial structures or metabolic pathways. Many viral diseases (like polio, measles, influenza) can be prevented through vaccination, which stimulates the immune system to develop memory against the virus. Fungal diseases (like ringworm, candidiasis) are caused by fungi, not protozoa; protozoa cause diseases like malaria and amoebiasis. Thus, statements 1 and 2 are correct.