Secretion of sebaceous glands is -

Correct Answer: A

Rationale: The correct answer is A: Oily. Sebaceous glands secrete an oily substance called sebum, which helps lubricate and waterproof the skin and hair. Sebum is composed of lipids and fatty acids, giving it an oily consistency. Choice B (Watery) is incorrect as sebaceous glands do not secrete a watery substance. Choice C (Creamy) is incorrect as sebum is not creamy in texture. Choice D (Mucoid) is incorrect as sebaceous glands do not secrete a mucoid substance. The oily nature of sebum is essential for maintaining skin health and function.

Correct Answer: B

Rationale: The correct answer is B: Areolar connective tissue. In the image, region '2' appears loose and has fibroblasts, collagen fibers, and elastic fibers, typical of areolar connective tissue. Areolar tissue is a loose connective tissue that provides support and elasticity. Rationale: 1. Areolar connective tissue is characterized by loose arrangement of cells and fibers, providing support and elasticity. 2. Presence of fibroblasts, collagen fibers, and elastic fibers in region '2' matches the characteristics of areolar connective tissue. 3. Areolar tissue is commonly found beneath the epithelial layers and around blood vessels and organs, supporting the body and connecting different tissues. Summary: A: Reticular connective tissue is more densely packed with reticular fibers and is found in organs like the spleen and lymph nodes. C: Stratified squamous epithelium is a type of epithelial tissue, which is not seen in region '2'.

Correct Answer: A

Rationale: Step-by-step rationale: 1. Melanin increases in concentration during sun exposure to protect the skin. 2. Option A is incorrect as melanin actually increases in concentration to protect against UV radiation. 3. Melanin is typically brown or black (B), released through melanosomes (C), and protects DNA from UV damage (D). 4. In summary, option A is the correct answer because melanin does not decrease in concentration during sun exposure; it increases to provide protection.

Correct Answer: D

Rationale: In thin skin, the epidermis contains 4 layers: stratum basale, spinosum, granulosum, and corneum. In thick skin, it contains an additional layer called stratum lucidum. Therefore, the correct answer is D. Option A is incorrect because thin skin has 4 layers. Option B is incorrect as thick skin has 5 layers. Option C is incorrect as thin skin has 4 layers and thick skin has 5 layers.

Correct Answer: B

Rationale: The correct answer is B: on the palms of the hands. This is because the palms of the hands have the highest concentration of merocrine sweat glands, which are responsible for regulating body temperature by producing sweat. The palms have a higher density of these glands compared to other areas listed in the choices. A: The chest does have sweat glands, but not the highest concentration compared to the palms. C: While the axillae (armpits) have a high concentration of apocrine sweat glands, merocrine glands are more abundant on the palms. D: The upper back also contains sweat glands, but not as densely packed as on the palms. In summary, the palms of the hands have the highest concentration of merocrine sweat glands, making them the correct choice.