Nokea
What is the primary function of the cardiovascular system?
- A. To transport oxygen and nutrients
- B. To remove waste products
- C. To regulate body temperature
- D. To fight infections
Correct Answer: A
Rationale: The correct answer is A: "To transport oxygen and nutrients." The primary function of the cardiovascular system is to transport oxygen, nutrients, and hormones to cells throughout the body and remove waste products. This system plays a crucial role in maintaining homeostasis by delivering essential substances to tissues and organs while eliminating metabolic waste. Choices B, C, and D are incorrect because although the cardiovascular system indirectly helps in removing waste products through circulation, its primary function is focused on transporting essential substances and not on regulating body temperature or fighting infections.
You may also like to solve these questions
Which vitamin is important for the absorption of iron?
- A. Vitamin C
- B. Vitamin D
- C. Vitamin K
- D. Vitamin B12
Correct Answer: A
Rationale: The correct answer is Vitamin C. Vitamin C is essential for the absorption of iron, especially from plant-based sources. It aids in converting non-heme iron (found in plants) into a form that is easier for the body to absorb. This is crucial in preventing iron-deficiency anemia, making Vitamin C a key nutrient for overall health. Vitamin D (choice B) is important for calcium absorption and bone health, not iron absorption. Vitamin K (choice C) plays a role in blood clotting and bone metabolism, not iron absorption. Vitamin B12 (choice D) is important for red blood cell formation and neurological function but is not directly involved in iron absorption.
What is the main function of the skeletal system?
- A. To produce red blood cells
- B. To protect internal organs and provide support
- C. To regulate body temperature
- D. To store calcium
Correct Answer: B
Rationale: The main function of the skeletal system is to provide structural support, protect internal organs, enable movement, and maintain the body's form. Choice A, 'To produce red blood cells,' is incorrect as the skeletal system's role in blood cell production is through the bone marrow, not its main function. Choice C, 'To regulate body temperature,' is incorrect as the skeletal system is not primarily responsible for regulating body temperature. Choice D, 'To store calcium,' is partially correct as the skeletal system does store calcium but this is not its main function; instead, it is essential for bone strength and muscle function.
Which of the following is not a component of the central nervous system?
- A. Brain
- B. Heart
- C. Retina
- D. Spinal cord
Correct Answer: B
Rationale: The central nervous system comprises the brain and spinal cord, responsible for processing and transmitting information. The retina, though part of the eye, is an extension of the central nervous system. However, the heart is part of the circulatory system, responsible for pumping blood throughout the body. Therefore, the correct answer is the heart as it is not a component of the central nervous system.
What is the function of the small intestine?
- A. To store bile
- B. To absorb nutrients
- C. To digest food
- D. To produce enzymes
Correct Answer: B
Rationale: The small intestine is the primary site for nutrient absorption in the digestive system. It is responsible for absorbing nutrients from the digested food into the bloodstream for distribution throughout the body. Therefore, the correct function of the small intestine is to absorb nutrients. Choice A is incorrect because the gallbladder stores bile, not the small intestine. Choice C is incorrect because the digestion process primarily occurs in the stomach and small intestine. Choice D is incorrect because while the small intestine does play a role in enzyme production, its primary function is nutrient absorption.
Which structure in the eye is responsible for focusing light on the retina?
- A. Cornea
- B. Lens
- C. Retina
- D. Pupil
Correct Answer: B
Rationale: The lens of the eye is responsible for focusing light onto the retina. It plays a crucial role in bending light rays to ensure that they converge on the retina, enabling clear vision. The cornea helps in focusing light, but the final adjustment and fine-tuning occur through the lens. The retina receives the focused light and converts it into neural signals for the brain to interpret. The pupil, on the other hand, controls the amount of light entering the eye by dilating or constricting.