What Is Seasonal Affective Disorder? Seasonal affective disorder (SAD) is depression that happens only at a specific time of year. With SAD, a person becomes depressed in fall or winter, when days are ...

What Are the Lungs and Respiratory System? The lungs and respiratory system allow us to breathe. They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out ...

Medically reviewed by: Melanie L. Pitone, MDThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab Most spider bites don't go all the ...

Medically reviewed by: Ricki S. Carroll, MDThis link opens in a new tab Learn About Genetics at Nemours Children's HealthThis link opens in a new tab Sanfilippo (san-fuh-LEE-po) syndrome is a rare ...

Medically reviewed by: Melanie L. Pitone, MDThis link opens in a new tab Learn About Emergency Medicine at Nemours Children's HealthThis link opens in a new tab Before you get behind the wheel, get ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab We see and hear about hearts ...

Medically reviewed by: Yamini Durani, MDThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab Even with these precautions in place, ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab The digestive system breaks ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab The endocrine system is made ...

The human body is an amazing machine. Learn more about it through movies, quizzes, articles, and more.

Medically reviewed by: Larissa Hirsch, MDThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab Hib infections in the U.S. are rare ...

Medically reviewed by: KidsHealth Medical ExpertsThis link opens in a new tab Learn About Primary Care Pediatrics at Nemours Children's HealthThis link opens in a new tab Every single person has a ...