This animation shows how the proton gradient across the mitochondrial membrane powers the ATP synthase enzyme to make ATP. It is the third of three animations about cellular respiration.

This animation shows how the enzyme complexes of the electron transport chain harvest energy from cofactor molecules to pump protons across the mitochondrial membrane and establish a chemical gradient. It is the second of three animations about cellular respiration.

This animation shows the reactions of the citric acid cycle, which splits off carbon atoms and generates energy-rich reduced forms of cofactor molecules. It is the first of three animations about cellular respiration.

This three-part animation series explores the biology of the virus SARS-CoV-2, which has caused a global pandemic of the disease COVID-19.

The world cut its daily carbon dioxide emissions by 17% at the peak of the pandemic shutdown last month, a new study found.

This film explores how life recovered after an asteroid wiped out the dinosaurs and how those events shaped the diversity of plants and mammals on Earth today.

For the first time, a blood test has been shown to help detect many types of cancer in a study of thousands of people with no history or symptoms of the disease.

To give rivers more room to sprawl, cities are keeping adjacent lands for limited uses such as parks that can flood when rivers rise.

An unplanned grand experiment is changing Earth. As people across the globe stay home to stop the spread of the new coronavirus, the air has cleaned up, albeit temporarily.

Hospitals are gearing up to test if a century-old treatment used to fight off flu and measles outbreaks in the days before vaccines, and tried more recently against SARS and Ebola, just might work for COVID-19, too: using blood donated from patients who’ve recovered.

A tiny fossil skull nicknamed “Wonderchicken” is giving scientists a rare glimpse at early ancestors of today’s birds. It may be the oldest known fossil from this group.

Scientists say they have used the gene editing tool CRISPR inside someone’s body for the first time, a new frontier for efforts to operate on DNA, the chemical code of life, to treat diseases.