Explainers | Science News for Students

Explainers

Background pieces on a broad range of pivotal topics

a close up photo of a baby wiping his nose

Mucus, snot and phlegm are made from the same thing and serve the same purpose. They’re a first line of defense against germs.

AntonioGuillem/iStockphoto

Body functions
 
Feb 20, 2019
Explainer: The benefits of phlegm, mucus and snot
a girl playing in a snowdrift

Snowflakes take a long journey down from the clouds in which they form. But it takes more than cold air and moisture to create them.

SbytovaMN/iStockphoto, adapted by L. Steenblik Hwang

Weather & Climate
 
Feb 14, 2019
Explainer: The making of a snowflake
a photo of a smiling family with a baby girl in the middle

We inherit genes from our parents. Genes are like a recipe that’s passed along from one generation to the next. But the number of genes doesn’t explain why we are more complex than simple animals or bacteria.

digitalskillet/iStockphoto

Genetics
 
Feb 8, 2019
Explainer: What are genes?
a photo of high-voltage electrical lines stretching towards the horizon to meet the support towers closer to the horizon

High-voltage electric lines are part of the giant network that makes up the electric grid.

Chris Hunkeler/Flickr (CC BY-SA 2.0)

Technology
 
Jan 24, 2019
Explainer: What is the electric grid?
a photo showing a supercell storm creating a tornado at the horizon of the picture

Rotating thunderstorms known as supercells are the storms that give rise to most tornadoes.

Graham Moore/iStockphoto

Weather & Climate
 
Jan 18, 2019
Supercell: It’s the king of thunderstorms
an aerial photo of a flooded street in Ho Chi Minh City, scooters and cars are driving through the floodwaters

Traffic keeps flowing on a flooded street in Ho Chi Minh City in Vietnam. Sea levels are rising around the world, but they are rising more quickly in some places than in others.

xuanhuongho/iStockPhoto

Weather & Climate
 
Jan 10, 2019
Explainer: Why sea levels aren't rising at the same rate globally
a photo of heavy rain falling on a colorful umbrella outside

Rain is just one part of the planet’s water cycle.

RomoloTavani/iStockphoto

Weather & Climate
 
Dec 6, 2018
Explainer: Earth’s water is all connected in one vast cycle
a photo of pipes used to transport water in a sewage treatement plant

Most people get their drinking water from lakes, rivers or groundwater aquifers. But before it flows out the tap, cities will typically treat the water in big industrial plants, as here, to purify it.

WangAnQi/iStockphoto

Pollution
 
Nov 29, 2018
Explainer: How is water cleaned up for drinking
a radar map showing hurricane Harvey's eyewall

Doughnut of intense storm activity swirls about Harvey’s eyewall (green ring at center with smattering of red and yellow). This radar imagery captured hours before the hurricane’s landfall near Rockport, Texas on August 26, 2017. 

National Weather Service, GR2 Analyst, M. Cappucci

Weather & Climate
 
Oct 12, 2018
Explainer: The furious eye(wall) of a hurricane or typhoon
A photo of an array of protein rich foods including red meat, fish, nuts, beans, eggs, chickpeas, avacado, spinach and broccoli

Many foods, such as the ones shown here, are rich in protein. In the body, proteins act as biochemical machines that do the work of cells.

samael334/iStockphoto

Body functions
 
Oct 3, 2018
Explainer: What are proteins?