Plan and conduct an investigation to provide evidence that feedback mechanisms maintain homeostasis.

  1. Health & Medicine

    Owww! World’s hottest chili leads to days of severe headaches

    A man ate one of the hottest peppers in the world. About a minute later, his head began pounding. See why they didn’t permanently disappear for days!

  2. Health & Medicine

    Obesity makes taste buds disappear — in mice, anyway

    Mice that gained excessive weight on a high-fat diet also lost one in four taste buds.

  3. Health & Medicine

    Explainer: What is a concussion?

    A concussion is a severe type of head injury that can damage a brain for weeks to years — perhaps even a lifetime.

  4. Health & Medicine

    Explainer: What is a hormone?

    Various tissues secrete special chemicals, known as hormones. They travel, usually in blood, to a particular distant site where they tell certain cells it’s time to go to work.

  5. Animals

    Scientists Say: Extremophile

    Some species can survive high heat, freezing cold or other extreme environments. Scientists call these organisms extremophiles.

  6. Health & Medicine

    Is your home chilly? This might just be healthy

    Feeling mildly cold (or a bit too warm) forces the body to adjust what it’s doing to maintain a healthy temperature. And that can do a body good, data now show.

  7. Health & Medicine

    Hibernation: Secrets of the big sleep

    Mammals from bears to squirrels hibernate the winter away. Learning how they do it might one day help people mimic aspects of it to heal from brain injuries or voyage to Mars.

  8. Animals

    Explainer: How brief can hibernation be?

    Many animals frequently slow body functions and drop their temperatures — sometimes for just a day. Is that hibernation, or just torpor? Are the two even related? Scientists disagree.

  9. Animals

    Scientists Say: Hibernation

    Hibernation is more than a deep sleep. Animals that hibernate lower their body temperature and reduce their body activities for months.

  10. Brain

    Explainer: What is dopamine?

    Dopamine is a chemical messenger that carries signals between brain cells. It also gets blamed for addiction. And a shortage of it gets blamed for symptoms of diseases such as Parkinson’s.

  11. Health & Medicine

    Seven tips for staying safe in frigid weather

    Maps? Check. Water? Check. Insulating clothes? Check. Here’s the checklist to consult before planning to trek out in the frigid cold.

  12. Oceans

    Creative ways to help coral reefs recover

    Coral reefs are under siege from threats ranging from climate change to explosives. But scientists are developing ways to rebuild reefs before they disappear.