What is a temporary loss of consciousness due to insufficient blood flow to the brain called?

Correct Answer: C

Rationale: Syncope, also known as fainting, is a temporary loss of consciousness caused by insufficient blood flow to the brain. It results from a brief interruption in the brain's blood supply, leading to a temporary loss of consciousness. The correct answer is C. A stroke, option A, is caused by a blockage or rupture of blood vessels in the brain, not insufficient blood flow. Seizure, option B, involves a sudden surge of electrical brain activity, not reduced blood flow. Coma, option D, is characterized by prolonged unconsciousness, not a temporary loss of consciousness due to insufficient blood flow.

Correct Answer: B

Rationale: The aorta is the correct answer because it is the main artery in the body that carries oxygenated blood away from the heart to the rest of the body. The pulmonary artery carries deoxygenated blood from the heart to the lungs for oxygenation. The superior and inferior vena cava are veins that carry deoxygenated blood from the body back to the heart. Therefore, choices A, C, and D are incorrect as they do not carry oxygenated blood away from the heart.

Correct Answer: B

Rationale: The correct answer is B: Moistening inhaled air. The cilia lining the respiratory tract primarily function to trap inhaled dust and debris, produce mucus, and propel the mucus upwards towards the throat for removal. Moistening inhaled air is primarily done by the mucous membranes in the nasal passages, which contain blood vessels that help warm and humidify the air as it passes through the nasal cavity. Therefore, the function of moistening inhaled air is not directly associated with the cilia in the respiratory tract, making it the correct choice in this scenario. Choices A, C, and D are incorrect as they are all functions carried out by the cilia in the respiratory tract.

Correct Answer: A

Rationale: During vigorous exercise, the muscles require more oxygen to produce energy for physical activity. The increased respiratory rate helps to deliver more oxygen to the working muscles to meet this demand. This process is essential for sustaining physical activity and preventing fatigue. Choice A is the correct answer as it accurately describes the purpose of the increased respiratory rate during vigorous exercise. Choices B, C, and D are incorrect. Choice B, 'Eliminate excess carbon dioxide more slowly,' is inaccurate as the primary reason for the increased respiratory rate during exercise is to meet the increased demand for oxygen, not to eliminate carbon dioxide. Choice C, 'Conserve energy for physical activity,' is incorrect because increasing the respiratory rate actually expends energy to meet the oxygen demand of the working muscles. Choice D, 'Decrease the amount of oxygen delivered to the body,' is incorrect as the increased respiratory rate is specifically to deliver more oxygen to the body during exercise.

Correct Answer: B

Rationale: The nephron is the correct answer as it is the microscopic functional unit of the kidney responsible for filtering blood. It is composed of a renal corpuscle (glomerulus and Bowman's capsule) and a renal tubule. The other options, such as (A) Ureter, (C) Renal pelvis, and (D) Bladder, do not play a role in filtering blood within the kidney. The ureter is a tube that carries urine from the kidney to the bladder. The renal pelvis is a part of the kidney where urine collects before entering the ureter. The bladder is an organ that stores urine until it is excreted from the body.