HS-LS1-2
Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.
- 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.
- Genetics
Explainer: How CRISPR works
Scientists are using a tool called CRISPR to edit DNA in all types of cells.
- Animals
Beware the tap of the narwhal’s tusk
A new video shows narwhals using their tusks to tap fish before eating them. They might be stunning their prey — or just playing with their food.
- Animals
How a flamingo balances on one leg
Flamingos are so good at balancing on just one leg that they can snooze that way with little effort.
- Earth
Tiny air pollutants inflame airways and harm heart
New studies show how tiny bits of air pollution, called particulate matter, can lead to health problems ranging from chronic runny noses to heart disease.
- Plants
Scientists Say: Guttation
When water vapor can’t escape a plant, it might force its way out through a process called guttation.
- Animals
Frog’s gift of grab comes from saliva and squishy tissue
What puts the grip in a frog’s high-speed strike? Quick-change saliva and a super-soft tongue, scientists find.
- Genetics
How to make a ‘three-parent’ baby
Scientists combined an egg, sperm and some donor DNA: The end result: what appears to be healthy babies.
- Animals
How birds know what not to tweet
How do birds perfect their pitches? The chemical dopamine spikes when they sing right, and dips when they drop a note, new data show.
- 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.
- Brain
Explainer: What is neurotransmission?
When brain cells need to pass messages to one another, they use chemicals called neurotransmitters. This sharing of chemical secrets is known as neurotransmission.
- Health & Medicine
Scientists Say: Bruxism
Some people clench their jaw when their stressed. People who do it a lot may have bruxism.
