Scientists Say
A weekly word defined, in a sentence and in context. Click here to find the alphabetized list.
- Animals
Scientists Say: Evolution
Evolution is how species change over time. Individuals in the group vary, and some will pass on their genes. Over time, the whole species changes.
- Brain
Scientists Say: Nucleus
Nucleus comes from the Latin term “nuc,” meaning nut or kernel. In science there are lots of nuclei. Every one of them is the center of something.
- Earth
Scientists Say: Earthquake
An earthquake is a sudden and sometimes violent shaking of the ground.
- Brain
Scientists Say: Narcotic
Scientists refer to a narcotic as a drug that stops pain, but the word can be used in other ways as well.
- Physics
Scientists Say: Gravity
Gravity is a fundamental force that attracts objects with mass to other objects with mass. It decreases with distance.
- Life
Scientists Say: Theory
A theory is an explanation of how part of the world works. It’s one that’s been tested many times and in many ways.
- Chemistry
Scientists Say: Plastic
Plastics are made of long polymer chains and can take on many shapes. Unfortunately, they stick around for a long time.
- Animals
Scientists Say: Amphibian
Amphibians are ectotherms that live dual lives — they start off in water, breathing with gills, and end up breathing air with lungs.
- Chemistry
Scientists say: Chemical
A chemical is anything made of two or more atoms bonded together in a fixed structure. Chemicals make up the world around us.
- Space
Scientists Say: Asteroid, meteor and meteorite
Asteroids, meteors and meteorites are all space rocks. But one is in orbit, another is in the atmosphere and the third is on the ground on Earth.
- Health & Medicine
Scientists Say: Vaccine
Vaccines help the body develop immunity to a disease. They are biological mixtures that imitate a disease so the body can defend itself.
- Agriculture
Scientists Say: Carbohydrate
Carbohydrates are molecules with carbon, oxygen and hydrogen. Animals break down these chemicals in food to get energy.
