This abstract array of blue, green, and orange swirls depicts an important bodily system, the lymphatic system, which produces immune cells and transports them throughout the bodies of all vertebrates ...

What am I looking at? This is a single human hepatocyte. Its two nuclei are in blue (1). The other colors in this image are stains of the actin protein and are depth-coded, with red being the closest ...

You may think of the small intestine as a smooth tube that winds its way through your abdomen. But if you were to look really closely at the inside of the intestine, you would see that it is lined ...

While this image might look like a multicolored tile floor, it is actually a cross section through the fingerlike bumps on the intestinal wall called villi. The cells within the villi, which you can ...

This furry face belongs to the caterpillar of an Automedon giant owl butterfly – which calls the forests of South America home. The butterfly that this caterpillar will transform into has striking ...

This neon marvel highlights the muscles of a developing aquatic invertebrate known as a moss animal, also known as a bryozoan – a member of the phylum Bryozoa. The organism gets its common name from ...

Skeletal muscle cells are long and thin and can contain multiple nuclei. These cells fuse end to end with their neighbors to form myotubes, which then collectively form muscle fibers. When bundled ...

Do you notice the tiny red-ringed dots in this image? Those little spots are HIV particles. They are concentrated on contact points in the brain between an infected immune cell and an uninfected ...

This cross section through several mouse testes shows how sperm are made and maintained. The testes are where sperm cells are made. A human male can produce between 70 million and 150 million sperm ...

Mesenteric adipose tissue is fat that surrounds the intestines in the abdomen of mammals. This tissue contains hematopoietic cells – a subset of stem cells that can turn into different kinds of blood ...

RSV is a common reparatory virus that can infect humans of any age but that’s especially dangerous in children and the elderly. The virus can cause more severe symptoms in these two populations ...

What am I looking at? This is an image of the blood vessels and pericytes in the spinal cord of a mouse. The blood vessels are shown in purple (1) and the pericytes in green (2). Biology in the ...