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Medical Knowledge & Clinical Science Flashcards

9 cards from real ECFMG practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 9 Medical Knowledge & Clinical Science flashcards as text
  1. What is the primary function of hemoglobin in the human body?

    Answer: Carrying oxygen to tissues

    Hemoglobin is a protein found in red blood cells that contains iron. Its primary function is to bind with oxygen in the lungs and transport it efficiently through the bloodstream to various tissues and organs throughout the body. This oxygen is vital for cellular respiration and energy production, making hemoglobin essential for life.

  2. Which organ is primarily responsible for insulin production?

    Answer: Pancreas

    The pancreas is a glandular organ located behind the stomach that plays a crucial role in both digestion and hormone production. Specifically, the beta cells within the islets of Langerhans in the pancreas are responsible for producing insulin. Insulin is a hormone essential for regulating blood glucose levels by facilitating glucose uptake into cells.

  3. What type of joint is the knee classified as?

    Answer: Hinge joint

    The knee joint is classified as a hinge joint, which primarily allows for movement in one plane, similar to a door hinge. This type of joint facilitates flexion (bending) and extension (straightening) of the leg. While it does allow for some limited rotation when flexed, its main function is uniaxial movement.

  4. Which vitamin deficiency causes scurvy?

    Answer: Vitamin C

    Scurvy is a disease caused by a severe deficiency of Vitamin C, also known as ascorbic acid. Vitamin C is essential for the synthesis of collagen, a crucial protein for connective tissues, wound healing, and maintaining healthy blood vessels, bones, and teeth. Without sufficient Vitamin C, these bodily functions are impaired, leading to characteristic symptoms.

  5. What is the normal range for adult human body temperature?

    Answer: 36.5°C to 37.5°C

    The normal range for adult human body temperature is generally considered to be between 36.5°C and 37.5°C (or 97.7°F to 99.5°F). While 37.0°C (98.6°F) is often cited as the average, individual temperatures can fluctuate slightly throughout the day and vary based on factors like activity level. Maintaining this narrow range is crucial for optimal physiological function.

  6. Which blood type is considered the universal donor?

    Answer: Type O negative

    Type O negative blood is considered the universal donor because its red blood cells lack A, B, and Rh antigens. This means it can be safely transfused to patients of any blood type without triggering an immune response, making it critically important in emergency situations when a patient's blood type is unknown. However, O negative individuals can only receive O negative blood.

  7. What is the main neurotransmitter involved in muscle contraction?

    Answer: Acetylcholine

    Acetylcholine is the primary neurotransmitter responsible for muscle contraction in the somatic nervous system. When an action potential reaches the neuromuscular junction, acetylcholine is released and binds to receptors on the muscle fiber, initiating a cascade of events that leads to muscle contraction. It also plays a crucial role in the autonomic nervous system and brain function.

  8. Which condition is characterized by the destruction of myelin sheaths in the central nervous system?

    Answer: Multiple sclerosis

    Multiple sclerosis (MS) is a chronic, autoimmune disease that affects the brain and spinal cord, which constitute the central nervous system. In MS, the immune system mistakenly attacks and damages the myelin sheath, the protective covering around nerve fibers. This demyelination disrupts the transmission of nerve impulses, leading to a wide range of neurological symptoms.

  9. Which electrolyte imbalance is commonly seen in patients with Addison’s disease?

    Answer: Hyponatremia and hyperkalemia

    Addison's disease is characterized by adrenal insufficiency, meaning the adrenal glands produce insufficient amounts of cortisol and often aldosterone. Aldosterone's primary role is to regulate sodium and potassium balance. A deficiency in aldosterone leads to increased sodium excretion (hyponatremia) and decreased potassium excretion (hyperkalemia) by the kidneys, which are hallmark electrolyte imbalances of the condition.

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Sources & references

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  1. usmle.org — Eligibility · verified Oct 2026
  2. ecfmg.org — Eligibility, registration deadline, score validity, renewal, test delivery, passing score, retake policy, score release, test dates, fees · verified Oct 2026
  3. fsmb.org — Eligibility · verified Oct 2026