Nokea
Which of the following illustrates a positive feedback mechanism?
- A. Maintaining blood pressure
- B. Uterine contractions during childbirth
- C. Body temperature control
- D. Control of blood sugar
Correct Answer: B
Rationale: The correct answer is uterine contractions during childbirth. This is an example of a positive feedback mechanism where the initial stimulus (contractions) leads to an increase in intensity and frequency, ultimately resulting in childbirth. In contrast, choices A, C, and D (maintaining blood pressure, body temperature control, and control of blood sugar) are examples of negative feedback mechanisms. These mechanisms work to maintain stability by counteracting any deviations from the set point, rather than amplifying the response like in a positive feedback mechanism.
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What does magnetic resonance imaging use?
- A. X-rays.
- B. a radio antenna.
- C. radioisotopes.
- D. high-frequency sound waves.
Correct Answer: D
Rationale: Magnetic resonance imaging (MRI) uses high-frequency sound waves to create detailed images of the inside of the body. X-rays (Choice A) use electromagnetic radiation, not sound waves, making it an incorrect choice. A radio antenna (Choice B) is used for communication, not for MRI imaging. Radioisotopes (Choice C) are used in nuclear medicine imaging techniques, not in MRI scans. Therefore, the correct answer is high-frequency sound waves (Choice D) as they are utilized in MRI technology to produce images.
Why are anatomy and physiology difficult to separate?
- A. Physiological functions depend on anatomical structures.
- B. Physiological functions in an organism are ongoing.
- C. Body parts provide structural support.
- D. Our understanding of physiology is changing more than our understanding of anatomy.
Correct Answer: A
Rationale: Anatomy and physiology are difficult to separate because physiological functions depend on anatomical structures. The correct answer highlights the interdependence between the two disciplines; physiological functions are carried out by anatomical structures. Choice B is incorrect as it only states a characteristic of physiological functions without addressing the relationship with anatomy. Choice C is incorrect as it talks about body parts providing structural support, which is not directly related to the interdependence of anatomy and physiology. Choice D is incorrect because the rate of change in understanding does not necessarily dictate the difficulty of separating the two disciplines.
Positive feedback mechanisms usually result in
- A. changes returning values away from a set point.
- B. stable conditions around a set point.
- C. unstable conditions.
- D. long-term changes.
Correct Answer: C
Rationale: Positive feedback mechanisms usually result in unstable conditions. In a positive feedback loop, the output enhances or amplifies the changes that are occurring, leading to a deviation from the initial set point. Therefore, positive feedback does not bring values back towards the set point (Choice A). Choice B is incorrect because positive feedback does not promote stability around a set point. Choice D is also incorrect as positive feedback mechanisms typically do not lead to long-term changes; instead, they intensify the initial change, causing instability.
Most of the terminology to name and describe body parts and their functions comes from
- A. Latin and Greek.
- B. English and Italian.
- C. Pictures drawn on the cave walls of our ancestors.
- D. The language of hunter-gatherers.
Correct Answer: A
Rationale: The correct answer is Latin and Greek. Medical terminology is largely derived from Latin and Greek roots. These languages have been foundational in the development of medical terminology due to the precision and descriptive nature of their vocabulary. Choice B, English and Italian, is incorrect because while some medical terms may have originated from these languages, the majority come from Latin and Greek. Choices C and D, pictures drawn on the cave walls of our ancestors and the language of hunter-gatherers, are both incorrect as they do not align with the historical origins of medical terminology.
What is the main function of the digestive system?
- A. Formation of cells
- B. Movement of body parts
- C. Absorption of nutrients
- D. Providing oxygen for the extraction of energy from nutrients
Correct Answer: C
Rationale: The correct answer is C: Absorption of nutrients. The main function of the digestive system is to break down food into nutrients that can be absorbed by the body. Choice A, 'Formation of cells,' is incorrect as cell formation is not the primary function of the digestive system. Choice B, 'Movement of body parts,' is incorrect as this is more related to the muscular system. Choice D, 'Providing oxygen for the extraction of energy from nutrients,' is incorrect because providing oxygen is primarily the function of the respiratory system, not the digestive system.