Correct Answer: B

Rationale: The correct answer is B. If an organism is AB, it indicates that it carries two different alleles. During gamete formation, each gamete receives only one allele from the pair present in the organism. Therefore, in this case, the possible gametes would be 'A' and 'B,' making 'AA' impossible. Choice A, 'AB,' is possible as each gamete can carry one of the alleles from the genotype. Similarly, 'BB' is also possible if one of the alleles separates into a gamete. Choice D, 'AB,' is essentially the same genotype as the organism and is a possible combination in the gametes.

Correct Answer: C

Rationale: The epidermis is the outermost layer of the skin and is avascular, meaning it does not contain blood vessels. It receives nutrients through diffusion from the underlying dermis. The hypodermis is the subcutaneous tissue beneath the dermis and contains blood vessels. The dermis is the layer of skin between the epidermis and hypodermis, which contains blood vessels, nerves, hair follicles, and sweat glands. 'Hyperdermis' is not a correct anatomical term and is not a layer of the skin, making it an incorrect choice for this question.

Correct Answer: C

Rationale: The correct answer is Covalent (C). In DNA, a covalent bond connects sugar and phosphate molecules. This bond involves the sharing of electron pairs between the atoms, providing stability to the DNA structure. Hydrogen bonds are important in DNA structure but are not the primary bond connecting sugar and phosphate. Ionic bonds involve the transfer of electrons, and 'overt' is not a term related to the bond connecting sugar and phosphate in DNA.

Correct Answer: B

Rationale: The correct answer is B: Endocrine system. The adrenal glands are part of the endocrine system, not the immune, lymphatic, or respiratory system. The endocrine system is responsible for producing and regulating hormones that control various bodily functions. The adrenal glands specifically produce hormones like cortisol and adrenaline, which are critical for the body's response to stress and metabolic processes. The immune system is responsible for defending the body against infections and diseases, the lymphatic system is involved in immunity and fluid balance, and the respiratory system is responsible for gas exchange in the body. Therefore, choices A, C, and D are incorrect in the context of the adrenal glands.

Correct Answer: D

Rationale: When human cells divide by meiosis, the resulting cells contain 23 chromosomes. This is because meiosis is a cell division process that reduces the chromosome number by half, resulting in cells with a haploid number of chromosomes. In humans, the diploid number of chromosomes is 46. Therefore, after meiosis, the resulting cells have 23 chromosomes, ensuring the correct chromosome number is restored upon fertilization. Choices A, B, and C are incorrect as they do not represent the correct chromosome number resulting from meiosis in human cells.