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How Scientists Count Farts

Middle school learnscience.org

Name Date

Predict

A fart is gas that leaves your body through your bottom. For many years, doctors said healthy people fart about 10 to 14 times a day. Do you think healthy people fart more than 14 times a day?

Circle one. Yes / No

Why?

Watch

  1. I’m farting for science!youtube.com/shorts/8OqwMEsxD38

Word of the day

Flatus (FLAY-tus). The science word for the gas in a fart.

Word partComes fromMeaning
fla-Latin flāreto blow
-tusLatin -tusthe act of
  • Inflate means to fill with air, like blowing up a balloon. Inflate comes from the same Latin root, flāre, “to blow.”
  • In Italian, fiato means breath. The word comes straight from Latin flātus.

Bonus word. Microbiome (MY-kroh-BY-ohm). All the tiny living things, like bacteria, that live in or on a body or in a place. Micro- means small, and bio- means life.

Questions

  1. For many years, doctors said healthy people fart about 10 to 14 times a day. Those numbers came from people keeping track of their own farts. A sensor is a tool that detects something. A sensor clipped to underwear counted an average of 32 farts a day. Why would people counting their own farts come up with fewer than the sensor?

    Hint. Think about the hours you spend asleep. Can you count anything while you sleep?

  2. The Smart Underwear sensor Raven wore in the video detects hydrogen, a gas found in farts. Where does the hydrogen gas in a fart come from?

    Circle one. Air you swallow / Bacteria in your gut / Your lungs

    Hint. Listen to what Raven says the bacteria in your gut do with your food.

  3. In the Smart Underwear study, the lowest count for one day was 4 farts. The highest count for one day was 59 farts. Why do scientists count farts in lots of people before they say what’s normal?

    Hint. Could one person’s count tell you what’s normal for other people?

  4. In the video, Raven asks, “What counts as a fart?” Scientists decide what counts before they start counting. Why do scientists need to agree on what counts as one fart before they compare their numbers?

    Hint. Imagine one scientist counts tiny farts and another scientist skips tiny farts. Could the two scientists’ numbers match?

Exit ticket

Scientists can ask people to keep track of their own farts, or scientists can measure farts with a sensor. Which gives scientists a better fart count, keeping track yourself or measuring with a sensor? Why?

Hint. Think about what people miss while they sleep, and how easy it is to lose count of something you do without noticing.

Sources