Which of the following describes the difference between prokaryotic and eukaryotic cells?

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: During embryonic development, all tissues originate from the three primary germ layers: ectoderm, mesoderm, and endoderm. These germ layers give rise to various tissues and organs in the developing embryo through a process called gastrulation. Epithelial, muscle, and connective tissues are derived from these germ layers during development. Therefore, choices A, B, and C are incorrect as tissues do not originate from a single type of tissue but rather from the embryonic germ layers which differentiate into various tissues and organs.

Correct Answer: C

Rationale: Sweat glands play a vital role in regulating body temperature by releasing a watery fluid that evaporates from the skin's surface. This evaporation process helps cool the body down by dissipating heat, which is essential for maintaining a stable internal temperature. Choice A is incorrect because sweat glands do not produce sebum but rather a watery fluid. Choice B is incorrect because sweating itself does not involve the constriction of blood vessels; instead, it promotes heat loss through evaporation. Choice D is incorrect as sweat glands do not thicken the epidermis for insulation but rather facilitate the cooling process through sweat evaporation.

Correct Answer: C

Rationale: Sebum is the waxy or oily substance produced by sebaceous glands. It helps lubricate the skin and hair, keeping them moisturized and protected. Keratin is a protein that makes up hair, skin, and nails, providing structure and strength. Melanin is a pigment that gives color to the skin, hair, and eyes, providing protection against UV radiation. Sweat is a watery fluid produced by sweat glands to help regulate body temperature by cooling the body through evaporation.

Correct Answer: C

Rationale: The correct answer is C: Flat bone. The kneecap (patella) is classified as a flat bone. Flat bones are thin, flattened bones that provide protection and offer a broad surface for muscle attachment. The patella fits this description as it is a flat, triangular bone located in front of the knee joint, protecting the knee and providing attachment points for muscles like the quadriceps. Choice A, long bone, is incorrect as long bones are typically found in the arms and legs, not in the knee area. Choice B, short bone, is incorrect as short bones are cube-shaped and are not characteristic of the patella. Choice D, irregular bone, is incorrect as irregular bones have complex shapes and do not apply to the flat, triangular structure of the patella.