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.
You may also like to solve these questions
What is the membrane on the surface of a lung called?
- A. visceral pleura
- B. parietal pleura
- C. visceral pericardium
- D. parietal pericardium
Correct Answer: A
Rationale: The correct answer is A: visceral pleura. The membrane covering the surface of the lungs is called the visceral pleura. It is a serous membrane that is in direct contact with the lung tissue. Choices B, C, and D are incorrect because the parietal pleura covers the inner surface of the chest wall and diaphragm, the visceral pericardium covers the surface of the heart, and the parietal pericardium is the outer layer of the pericardium surrounding the heart, respectively.
The recent discovery of taste receptors that detect sweetness in the small intestine illustrates that
- A. chemical responses occur in various parts of the body.
- B. new discoveries about anatomy and physiology are still being made.
- C. everything about anatomy and physiology has been discovered.
- D. the molecular and cellular level is crucial in anatomy and physiology.
Correct Answer: B
Rationale: The recent discovery of taste receptors in the small intestine illustrates that new discoveries about anatomy and physiology are still being made. This finding demonstrates that our understanding of the human body is continuously evolving. Choice A is incorrect because the discovery does not imply that chemical responses occur in only one part of the body but rather showcases a specific new discovery. Choice C is incorrect as it is highly improbable that everything about anatomy and physiology has been discovered given the complexity of the human body. Choice D is incorrect as while the molecular and cellular level is important in anatomy and physiology, the primary focus of this discovery is on the new findings about the taste receptors in the small intestine.
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.
Signs of aging at the cellular level are
- A. graying hair, waning strength, and wrinkles.
- B. unrepaired DNA and abnormal proteins.
- C. impaired cell division and the ability to break down and recycle worn cell parts.
- D. a fatty liver and clogged blood vessels.
Correct Answer: C
Rationale: The correct answer is 'impaired cell division and the ability to break down and recycle worn cell parts.' Aging at the cellular level involves reduced efficiency in cell division and the breakdown/recycling of cellular components, leading to functional decline. Choices A, B, and D are incorrect because they involve external physical manifestations or organ-specific issues rather than cellular-level changes associated with aging.
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.