ATI RN
Questions About the Integumentary System Questions
Question 1 of 5
Erection of the hairs during extreme cold, heat injury or anger etc. by the contraction of arrector pili muscles due to the effects of -
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.
Question 2 of 5
The major constituent of horns, nails, hairs and feathers of birds is-
Correct Answer: B
Rationale: The correct answer is B: Keratin. Keratin is a fibrous structural protein found in the horns, nails, hairs, and feathers of birds. It provides strength and flexibility to these structures. Collagen (A) is a different protein found in connective tissues. Mucin (C) is a glycoprotein found in mucus. Cuticle (D) is a protective outer layer found in plants and insects, not in the mentioned structures. Therefore, based on the composition and function of horns, nails, hairs, and feathers, keratin is the most appropriate choice.
Question 3 of 5
Huxley's layer is found in -
Correct Answer: B
Rationale: The correct answer is B: Root of the hair. Huxley's layer is a layer of cells located in the outer root sheath of the hair follicle. It is named after Thomas Huxley, a renowned biologist. This layer plays a role in the formation and growth of the hair. The other choices are incorrect because Huxley's layer specifically refers to a layer found in the root of the hair, not in the shaft or wall of the hair follicle. Choice D is incorrect as it denies the existence of Huxley's layer in any part of the hair structure.
Question 4 of 5
Which layer of the epidermis has transparent cytoplasm-
Correct Answer: B
Rationale: The correct answer is B: Stratum lucidum. This layer of the epidermis is characterized by its clear, transparent cytoplasm due to the presence of eleidin, a protein that replaces the keratohyalin in the granules of the stratum granulosum. Stratum malpighi (A) refers to the basal layer, stratum granulosum (C) contains granules with keratohyalin, and stratum corneum (D) is the outermost layer composed of dead keratinocytes. The transparency of cytoplasm is a unique feature of the stratum lucidum, making it the correct choice.
Question 5 of 5
All of the following are true of perspiration produced by merocrine sweat glands, except that it
Correct Answer: A
Rationale: The correct answer is A because merocrine sweat glands produce odorless sweat. The body odor associated with sweating is caused by apocrine sweat glands, not merocrine glands. Merocrine sweat helps prevent bacterial growth (B) through its antimicrobial properties. It contains water and waste products (C) such as urea and salts. Merocrine sweat is mostly water (D), aiding in cooling the body through evaporation. Therefore, A is incorrect as merocrine sweat does not produce body odor.