30 April 2015, 10:57 PM ET
Water fluoridation is the addition of the chemical fluoride to public water supplies, for the purpose of reducing cavities. The process has caused controversy for more than 60 years.
30 April 2015, 10:44 PM ET
This may be the most important system in the body. Without the ability to reproduce, a species dies.
30 April 2015, 01:27 AM ET
Mitochondria are specialized cellular structures that power various functions.
30 April 2015, 01:21 AM ET
Visible light is the portion of the electromagnetic spectrum that we can see. We perceive the energy as colors.
28 April 2015, 11:11 PM ET
Guinea pigs are a domesticated species of rodent that are popular as pets — and food. These animals no longer exist in the wild.
28 April 2015, 10:23 PM ET
Batteries power everything from your smartphone to your car, but do you know how they work?
28 April 2015, 07:33 PM ET
Archaeopteryx was an evolutionary link between dinosaurs and birds.
28 April 2015, 01:03 AM ET
Crunchy, crispy celery is well known for being low in calories, but its health benefits go far beyond use as a diet food.
27 April 2015, 12:42 AM ET
Risperdal (generic name risperidone) is an antipsychotic drug prescribed to treat schizophrenia, bipolar disorder and some behavioral problems in children with autism.
24 April 2015, 07:59 PM ET
Pigs are mammals with stocky bodies, flat snouts, small eyes and large ears. They are highly intelligent, social animals, and are found all over the world.
22 April 2015, 10:10 PM ET
Listeriosis is a bacterial infection typically caused by eating contaminated food.
22 April 2015, 07:03 PM ET
The human digestive system converts food into nutrients that the body needs.
22 April 2015, 06:56 PM ET
Lactose intolerance is not the same as milk allergy
22 April 2015, 09:37 AM ET
If there's a beast swimming in the Scottish lake, it has proved quite elusive.
21 April 2015, 05:03 PM ET
Earth Day is an annual event, observed on April 22, that celebrates the planet's environment and raises public awareness about pollution.
20 April 2015, 11:52 PM ET
Abdominal pain, bloating and gas all symptoms of IBS
20 April 2015, 11:02 PM ET
Earthquakes occur every day, but most people don't notice the small ones. Here's what causes earthquakes.
13 April 2015, 07:38 PM ET
Dogs are part of a large taxonomic family called Canidae, which also includes wolves, coyotes, foxes and jackals. Members are called canids. Domestic dogs are a subspecies called Canis lupus familiaris.
11 April 2015, 12:50 AM ET
Brown rice is a highly nutritious grain. It is good for the heart, aids digestion and may reduce the risk of cancer, diabetes and high cholesterol.
10 April 2015, 09:42 PM ET
Acid reflux disease, also called gastroesophageal reflux disease (GERD), is a chronic condition that occurs when stomach contents wash up into the throat.
09 April 2015, 06:13 PM ET
Hemp is a non-drug variety of the Cannabis plant with many uses.
07 April 2015, 11:35 PM ET
THC is the main mind-altering ingredient found in the Cannabis plant.
07 April 2015, 11:26 PM ET
Lung cancer is the deadliest type of cancer, causing more than 150,000 deaths annually in the United States. Smoking is the No. 1 cause of lung cancer.
07 April 2015, 07:14 PM ET
Quadratic equations are basic to algebra and are the math behind parabolas, projectiles, satellite dishes and the golden ratio.
06 April 2015, 10:13 PM ET
Quinoa, a plant from the Andes, is packed with protein, fiber and various vitamins and minerals.
06 April 2015, 09:41 PM ET
Radio waves are a type of electromagnetic radiation. The best-known use of radio waves is for communication.
06 April 2015, 07:44 PM ET
Prostate cancer is one of the most common forms of cancer in men: Almost 240,000 men in the United States are diagnosed with prostate cancer each year.
02 April 2015, 11:45 PM ET
Malignant mesothelioma is a cancer of the thin layer of tissue that covers the heart, lungs and other internal organs.
31 March 2015, 07:17 PM ET
Ultraviolet light is a type of electromagnetic radiation. These high-frequency waves can damage living tissue.
31 March 2015, 04:24 PM ET
Pregnancy lasts about 40 weeks and is divided into three stages, or trimesters, each with unique symptoms and changes in the mother's body and in fetal development.
30 March 2015, 07:49 PM ET
Science is a systematic and logical approach to discovering how things in the universe work.
26 March 2015, 12:25 PM ET
The human brain is the command center for the human nervous system.