Nokea
Which element is essential for the formation of hemoglobin?
- A. Calcium
- B. Iron
- C. Potassium
- D. Sodium
Correct Answer: B
Rationale: The correct answer is Iron. Iron is essential for the formation of hemoglobin, the protein in red blood cells that binds and transports oxygen throughout the body. Calcium (Choice A), Potassium (Choice C), and Sodium (Choice D) are not directly involved in the formation of hemoglobin and its oxygen-carrying function.
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What is the best tool to measure the volume of a solid?
- A. Triple beam balance
- B. Measuring wheel and mathematical formula
- C. Graduated cylinder
- D. Measuring wheel
Correct Answer: C
Rationale: A graduated cylinder is the most suitable tool to measure the volume of both liquids and solids. It works by measuring the displacement of water when the solid is submerged in the graduated cylinder. Choice A, the triple beam balance, is used to measure mass, not volume. Choice B, using a measuring wheel and mathematical formula, is typically used to measure distance or area, not volume. Choice D, a measuring wheel, is used to measure distance, making it inappropriate for measuring the volume of a solid.
Which of the following hormones is responsible for regulating blood sugar levels?
- A. Insulin
- B. Adrenaline
- C. Cortisol
- D. Melatonin
Correct Answer: A
Rationale: Insulin is the hormone responsible for regulating blood sugar levels by facilitating the uptake of glucose into cells. Insulin helps lower blood sugar levels by promoting the storage of glucose in the liver, muscle, and fat cells. Adrenaline, cortisol, and melatonin do not directly regulate blood sugar levels. Adrenaline is involved in the fight-or-flight response, cortisol is a stress hormone that affects metabolism, immune response, and anti-inflammatory actions, while melatonin regulates sleep-wake cycles.
Which of the following is not a biological macromolecule?
- A. Glycoproteins
- B. DNA
- C. Phospholipid
- D. Glucose
Correct Answer: D
Rationale: Glucose is a monosaccharide, which is a simple sugar and not a macromolecule. Glycoproteins, DNA, and phospholipids are all examples of biological macromolecules. Glycoproteins are proteins covalently bonded to carbohydrates, DNA is a nucleic acid, and phospholipids are lipids that contain a phosphate group.
Which part of the nervous system controls the 'fight or flight' response?
- A. Central nervous system
- B. Peripheral nervous system
- C. Autonomic nervous system
- D. Sympathetic nervous system
Correct Answer: D
Rationale: The correct answer is the sympathetic nervous system. It controls the 'fight or flight' response by preparing the body for stressful situations. The central nervous system (Choice A) consists of the brain and spinal cord but does not directly control the 'fight or flight' response. The peripheral nervous system (Choice B) includes nerves outside the brain and spinal cord, while the autonomic nervous system (Choice C) regulates involuntary bodily functions but is not specific to the 'fight or flight' response.
What is the function of the adrenal glands?
- A. To regulate metabolism
- B. To produce bile
- C. To produce red blood cells
- D. To regulate blood glucose
Correct Answer: D
Rationale: The correct answer is D: To regulate blood glucose. The adrenal glands play a crucial role in regulating blood glucose levels and the body's response to stress. Choice A, 'To regulate metabolism,' is incorrect as the primary role of the adrenal glands is not directly related to metabolism regulation. Choice B, 'To produce bile,' is incorrect because bile is produced by the liver, not the adrenal glands. Choice C, 'To produce red blood cells,' is also incorrect as the production of red blood cells primarily occurs in the bone marrow, not the adrenal glands.