a blood clot stimulating further clotting is an example of

ATI RN

ATI Anatomy and Physiology Online Practice

1. Which of the following best describes a blood clot stimulating further clotting?

A. a positive feedback mechanism.
B. a negative feedback mechanism.
C. a process turning itself off.
D. nervous system communication

Correct answer: A

Rationale: A blood clot stimulating further clotting is an example of a positive feedback mechanism. In positive feedback, the response enhances or amplifies the original stimulus, leading to an increase in the activity. In this case, the formation of a blood clot triggers more clotting activity, creating a cycle of increasing clot formation. Negative feedback mechanisms, on the other hand, work to maintain homeostasis by counteracting changes. Choices B, C, and D are incorrect as they do not accurately describe the situation of a blood clot stimulating further clotting.

2. An investigator who conducts an experiment to determine how temperature changes affect the rate at which the heart beats is most likely a(n)

A. anatomist.
B. physiologist.
C. chemist.
D. biochemist.

Correct answer: B

Rationale: The correct answer is 'physiologist.' A physiologist studies how the body functions under normal and abnormal conditions, including how temperature changes can affect physiological processes like heart rate. An anatomist focuses on the structure of organisms rather than their functions, making choice A incorrect. Choices C and D are also incorrect as they are more related to the study of chemicals and biochemistry, which are not directly relevant to investigating the effects of temperature on heart rate.

3. 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.

4. 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.

5. Which of the following are vital signs?

A. Body temperature, blood pressure, and pulse rate
B. Appearance of the skin, red blood cell count, oxygen level
C. Body weight, age, gender
D. Visual acuity and auditory sharpness

Correct answer: A

Rationale: The correct answer is A: Body temperature, blood pressure, and pulse rate. Vital signs are measurements that indicate the body's basic functions and are essential indicators of health. Body temperature, blood pressure, and pulse rate are classic vital signs routinely checked in medical settings to assess a person's overall health status. Choices B, C, and D are not considered vital signs. The appearance of the skin, red blood cell count, and oxygen level may provide valuable health information but are not classified as vital signs. Similarly, body weight, age, and gender are important factors in healthcare but are not vital signs. Visual acuity and auditory sharpness relate to sensory functions and are not typically categorized as vital signs.