Primary function of sweat glands is

Correct Answer: A

Rationale: The correct answer is A: Thermoregulation. Sweat glands help regulate body temperature by producing sweat, which evaporates and cools the body. Osmoregulation (B) is the regulation of water and solute concentrations in the body, not the primary function of sweat glands. Excretion (C) is the elimination of waste products, which is not the primary function of sweat glands. "None of the above" (D) is incorrect as sweat glands do play a significant role in thermoregulation.

Correct Answer: C

Rationale: The correct answer is C: Below the tail. Perineal glands are located in the perineal region, which is the area between the anus and the external genitalia. This location is below the tail in animals. Choice A is incorrect because perineal glands are not situated in the rectum. Choice B is incorrect as perineal glands are not near mammary glands. Choice D is incorrect as perineal glands are not located in the subcutaneous fat layer. Therefore, the correct location of perineal glands is below the tail.

Correct Answer: D

Rationale: The correct answer is D because the folder upper part of the dermis is composed of both skin papilla and hair papilla. Skin papilla plays a role in nourishing the epidermis, while hair papilla supports hair growth. Choice A, skin papilla only, is incorrect as it does not account for the hair papilla's presence. Choice B, hair papilla only, is also incorrect as it neglects the role of the skin papilla. Choice C, dermal papilla only, is incorrect as it does not specify the individual components involved in the upper part of the dermis. Thus, the correct answer is D, which accurately reflects the presence of both skin papilla and hair papilla in the folder upper part of the dermis.

Correct Answer: B

Rationale: Step 1: Arrector pili muscles are responsible for hair erection. Step 2: Sympathetic nervous system controls arrector pili muscles. Step 3: Adrenaline is released in response to stress, cold, heat, or anger. Step 4: Adrenaline activates sympathetic nervous system. Step 5: Sympathetic stimulation causes contraction of arrector pili muscles, leading to hair erection. Therefore, the correct answer is B: Adrenaline and sympathetic stimulation. Summary: - A: Adrenaline alone is not sufficient as it needs to activate the sympathetic nervous system. - C: Sympathetic stimulation alone does not explain the role of adrenaline. - D: Calcitiotinin is not involved in the contraction of arrector pili muscles.

Correct Answer: D

Rationale: The correct answer is D because the integument of a rabbit serves multiple functions. It conserves heat in winter by providing insulation, loses excess heat during summer through mechanisms like vasodilation, and regulates body temperature by adjusting blood flow and fur density. Choice A is correct but incomplete, as the integument also helps in thermoregulation. Choice B is incorrect as the integument helps in both heat conservation and dissipation. Choice C is also incorrect as the integument does more than just regulating body temperature, such as protecting against external factors and providing sensory functions.