Heart Rate, Stroke Volume and Cardiac Output · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

How much blood your heart pumps per minute

Science · The Human Body · ages 15-16
Name ______________________   Date ____________

  1. Stroke volume is 70 cm3 and pulse is 72 beats per minute. Calculate cardiac output in mL per minute.

    Answer: ______________

  2. What units suit a cardiac output of 5040?

    • Beats per minute
    • mL per beat
    • mL per minute

  3. Which statement gives cardiac output?

    • Stroke volume times heart rate
    • Stroke volume plus heart rate
    • Heart rate divided by stroke volume

  4. An athlete has a stroke volume of 70 mL and a heart rate of 72 beats per minute. Calculate the cardiac output in mL/min.

    Answer: ______________

  5. Which change boosts cardiac output most during exercise?

    • Heart rate, roughly tripling to push more blood per minute
    • Stroke volume, which multiplies tenfold
    • Blood pressure, which stays flat
    • Breathing rate, which slows down

  6. A cardiac output of 6000 mL/min comes from a heart rate of 75 bpm. What is the stroke volume in mL?

    Answer: ______________

  7. During a sprint, which quantity changes most to raise cardiac output?

    • Blood volume, which doubles
    • Stroke volume, which rises slightly
    • Heart rate, which roughly triples

  8. During hard exercise a stroke volume of 80 mL pairs with a heart rate of 150 bpm. Calculate cardiac output in mL/min.

    Answer: ______________

  9. A student divides stroke volume by heart rate and labels it mL per minute. What are the two mistakes?

    • Should divide heart rate by stroke volume instead
    • Should multiply, and the units would then work out
    • Should add, and drop the units

  10. In hard exercise a stroke volume of 80 mL pairs with a heart rate of 150 beats per minute. Calculate cardiac output in mL per minute.

    Answer: ______________

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Answer key

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How much blood your heart pumps per minute W1-mt_mjrPFHgvfx-s1

  1. 5040 · Multiply 70 by 72 to get 5040 mL per minute.
  2. mL per minute · Output is a volume per minute, so mL per minute fits.
  3. Stroke volume times heart rate · Output is volume per beat multiplied by beats per minute.
  4. 5040 · Multiply stroke volume by heart rate: 70 x 72 = 5040 millilitres per minute.
  5. Heart rate, roughly tripling to push more blood per minute · Heart rate climbs most, with stroke volume rising too, sending extra oxygen to muscles.
  6. 80 · Divide cardiac output by heart rate: 6000 / 75 = 80 mL per beat.
  7. Heart rate, which roughly triples · Heart rate is the biggest lever, with stroke volume adding a smaller rise.
  8. 12000 · 80 x 150 = 12000 millilitres per minute, or 12 litres per minute.
  9. Should multiply, and the units would then work out · Only multiplication gives volume per minute, which the units confirm.
  10. 12000 · Multiply 80 by 150 to get 12000 mL per minute, or 12 litres per minute.
Worksheet · LightMySky