Nokea
Which concentration unit depends on pressure?
- A. ppm
- B. ppb
- C. molarity
- D. molarity, ppb, and ppm
Correct Answer: C
Rationale: The correct answer is 'C: molarity.' Molarity is the concentration unit that depends on pressure. In molarity, the concentration of a solution is expressed as the number of moles of solute per liter of solution. This means that changes in pressure can affect the volume of the solution and consequently the concentration. Choices A and B, ppm (parts per million) and ppb (parts per billion), respectively, are independent of pressure variations as they are based on mass ratios. Therefore, molarity is the only concentration unit listed that is directly influenced by changes in pressure.
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Which of the following is an example of a flat bone?
- A. Femur
- B. Scapula
- C. Humerus
- D. Tibia
Correct Answer: B
Rationale: The correct answer is B, the Scapula. Flat bones, such as the scapula, are thin, flattened bones that provide protection to internal organs and serve as attachment points for muscles. The other choices, femur, humerus, and tibia, are examples of long bones, which are characterized by their elongated structure and are primarily involved in supporting weight and facilitating movement.
A scientist wants to conduct quantitative research. Which method should they use?
- A. Collecting patient narratives.
- B. Tracking the dosage of a drug and its blood levels in the patient.
- C. Observing a patient's physical changes.
- D. Writing journal notes about the research experience.
Correct Answer: B
Rationale: In quantitative research, numerical data is collected and analyzed. Choice B, tracking the dosage of a drug and its blood levels in the patient, involves collecting quantitative data, making it the correct method. Choices A, C, and D involve qualitative data such as narratives, physical observations, and journal notes, which do not align with the quantitative research method.
Which of the following is responsible for producing antibodies?
- A. Red blood cells
- B. White blood cells
- C. Platelets
- D. Plasma
Correct Answer: B
Rationale: White blood cells are responsible for producing antibodies. Antibodies are essential components of the immune system that help the body combat infections by identifying and neutralizing harmful pathogens. Red blood cells are primarily responsible for carrying oxygen, platelets are involved in blood clotting, and plasma is the liquid component of blood that carries nutrients and hormones.
Which part of the brain controls the coordination of muscle movements?
- A. Cerebrum
- B. Cerebellum
- C. Thalamus
- D. Medulla oblongata
Correct Answer: B
Rationale: The cerebellum is the part of the brain responsible for controlling the coordination of muscle movements and helping to maintain balance. It receives information from the sensory systems, the spinal cord, and other parts of the brain to regulate voluntary movements. The cerebrum (choice A) is primarily responsible for higher brain functions such as thinking and decision-making, not muscle coordination. The thalamus (choice C) acts as a relay station for sensory information but is not directly involved in muscle coordination. The medulla oblongata (choice D) is responsible for regulating vital autonomic functions like breathing and heart rate, rather than muscle coordination.
Which of the following organelles is responsible for food and water storage in the cell?
- A. Centriole
- B. Lysosome
- C. Ribosome
- D. Vacuole
Correct Answer: D
Rationale: The correct answer is D, Vacuole. Vacuoles are membrane-bound organelles responsible for the storage of various substances such as food, water, and waste in a cell. They help maintain the cell's turgidity and regulate the movement of substances within the cell. Choice A, Centriole, is involved in cell division and organization of microtubules but not food and water storage. Choice B, Lysosome, contains digestive enzymes for breaking down cellular waste material and foreign invaders. Choice C, Ribosome, is involved in protein synthesis rather than storage of food and water.