In mammals maximum energy is lost by the

Correct Answer: C

Rationale: The correct answer is C: Skin. In mammals, maximum energy is lost through the skin in the form of heat. This is due to the process of thermoregulation, where excess body heat is released through the skin to maintain a stable internal temperature. Respiration (choice A) is essential for energy production, urine (choice B) primarily eliminates waste products, and stool (choice D) is the result of undigested food. Skin, on the other hand, plays a crucial role in regulating body temperature and dissipating excess energy in the form of heat, making it the primary route for energy loss in mammals.

Correct Answer: A

Rationale: The correct answer is A: Panniculus carnosus. This muscle is responsible for moving and shaking the skin, particularly in animals. It is a thin layer of muscle found in the subcutaneous tissue. It contracts to create goosebumps and aid in thermoregulation. The other choices, B: Collagen fibers, C: Sphincter muscles, and D: Arrector pili, do not directly move and shake the skin. Collagen fibers provide structural support, sphincter muscles control the opening and closing of passages, and arrector pili are responsible for hair erection, not skin movement.

Correct Answer: C

Rationale: The correct answer is C: Columnar. The cells of stratum malpighi are columnar in shape as they are tall and rectangular, providing structural support and protection to the underlying layers of skin. The other choices are incorrect because A: Oval, B: Flat, and D: Spherical do not accurately describe the shape of cells in stratum malpighi. The cells in this layer are specifically columnar to serve their function in the epidermis.

Correct Answer: B

Rationale: The correct answer is B because scar tissue is primarily composed of collagen fibers, which are produced by fibroblasts during the wound healing process. Collagen fibers provide structural support and help in tissue repair. Scar tissue also has relatively few blood vessels compared to normal tissue. A: Increased numbers of fibroblasts alone do not directly result in scar tissue formation. C: The stratum germinativum is part of the epidermis and not directly involved in the formation of scar tissue. D: Scar tissue does not involve an increase in epidermal layers; it is mainly about the dermal layer with collagen deposition.

Correct Answer: C

Rationale: The correct answer is C: Eponychium. The eponychium is the cuticle surrounding the nail, providing protection and sealing the nail bed. The free edge (Choice A) refers to the tip of the nail, not the cuticle. The lunula (Choice B) is the white, crescent-shaped area at the base of the nail and is not the cuticle. Epicondyle (Choice D) is a bony projection near a joint and is not related to the cuticle. Therefore, the eponychium is the correct answer as it specifically refers to the cuticle around the nail.