cells

Without a good definition of life, how do we look for it on alien planets? Steven Strogatz speaks with Robert Hazen, a mineralogist and astrobiologist, and Sheref Mansy, a chemist, to learn more.

Was the addition of mitochondria a first step in the formation of complex cells or one of the last? A new study of bacteria tries to answer this contentious question in evolutionary biology.

The immune system protects us from a full spectrum of pathogens, but without balance, it can end up hurting us over time, too. The immunologist Shruti Naik explains how our defenses can turn on us.

With self-generated gradients of chemicals and physical tension, cells in the body steer themselves to vital destinations.

A 3D digital model of a “minimal cell” leads scientists closer to understanding the barest requirements for life.

Molecular detective work is zeroing in on the origins of sexual reproduction. The protein tools for cell mergers seem to have long predated sex — so what were they doing?

A mathematical model shows how a thermodynamic mechanism could have made protocells split in two.

The computational biologist Anne Carpenter creates software that brings the power of machine learning to researchers seeking answers in mountains of cell images.

The evolution of a defensive gland in beetles shows how organs can arise from novel cells carving out new functional niches for their neighbors.