which part of the nephron is closest to the collecting duct

ATI RN

ATI Anatomy and Physiology

1. Which part of the nephron is closest to the collecting duct?

A. Distal convoluted tubule (DCT)
B. Bowman's Capsule
C. Afferent Arteriole
D. Proximal Convoluted Tubule (PCT)

Correct answer: A

Rationale: The correct answer is the Distal convoluted tubule (DCT). The DCT is the part of the nephron closest to the collecting duct, where the final adjustments to electrolyte and fluid balance are made. Bowman's Capsule is located at the beginning of the nephron, where filtration of blood occurs. The Afferent Arteriole brings blood to the glomerulus for filtration. The Proximal Convoluted Tubule (PCT) is situated after the Bowman's Capsule and is not the part closest to the collecting duct.

2. What causes wrinkled and sagging skin?

A. Drinking too much water
B. Heredity alone
C. Loss of subcutaneous fat and reduced levels of elastin and collagen
D. Excess subcutaneous fat

Correct answer: C

Rationale: Wrinkled and sagging skin is primarily caused by the loss of subcutaneous fat and reduced levels of elastin and collagen in the skin. Choice A is incorrect as drinking too much water does not lead to wrinkled and sagging skin. Choice B is incorrect because heredity alone does not cause this condition. Excess subcutaneous fat, as mentioned in Choice D, can contribute to a different skin appearance, such as puffiness, but not wrinkled and sagging skin.

3. Which of the following is a result of stimulation of the sympathetic nervous system?

A. decreased blood flow to the skeletal muscles
B. increased cardiac output
C. decreased respiratory rate
D. increased urinary output

Correct answer: B

Rationale: Stimulation of the sympathetic nervous system leads to an increase in cardiac output. When the sympathetic nervous system is activated, it causes the heart to beat faster and with more force, leading to an increased cardiac output. Choices A, C, and D are incorrect because the sympathetic nervous system does not cause decreased blood flow to the skeletal muscles, decreased respiratory rate, or increased urinary output.

4. What do positive feedback mechanisms do?

A. Cause long-term changes.
B. Move conditions away from the normal state.
C. Bring conditions back to the normal state.
D. Usually produce stable conditions.

Correct answer: B

Rationale: Positive feedback mechanisms amplify or increase changes in a system, moving conditions away from the normal state. This makes choice B the correct answer. Choice A is incorrect as positive feedback does not cause long-term changes but rather accelerates deviations from the norm. Choice C is incorrect because positive feedback does not bring conditions back to normal; instead, it amplifies deviations. Choice D is incorrect as positive feedback does not usually lead to stable conditions but rather to further deviations from the normal state.

5. In the early days, healers transitioned from superstition and magic to using natural chemicals in the field of medicine.

A. True
B. False
C. Not Sure
D. None of the above

Correct answer: A

Rationale: The statement is true. The field of medicine evolved as early healers moved away from superstition and magic, instead focusing on natural chemicals to treat illnesses. This transition marked a shift towards a more scientific and evidence-based approach to healthcare. This historical transition is well-documented in the evolution of medicine. Choice B is incorrect because the statement accurately reflects the historical development of medicine. Choice C is incorrect as the historical transition from superstition to natural chemicals is a well-documented aspect of the evolution of medicine. Choice D is incorrect as the statement provided is true.