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 see here as multicolored circles within the purple or blue outlines, are very important for the proper function of the intestine as a whole.

An Intestinal Mosaic

This little mantis looks as if it might be posing for Instagram. However, with its wings extended like this, it is actually getting ready to defend itself.

Demure Mantis

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 with thousands of tiny fingerlike bumps that are designed to increase the surface area of the intestine’s inner wall. These bumps are called villi, and they play an important role in absorbing nutrients into your bloodstream to keep you healthy.

Livin’ la Villi Loca

These multicolored cells are from the liver of a mouse; the liver is one of the most functionally diverse organs. These cells are responsible for filtering the blood, as well as producing important substances that aid in digestion, metabolism, and much more.

Lively Liver 

This dark chasm looks like a hole in the center of a brightly colored tapestry, but it’s actually a central vein in the liver of a mouse.  The liver is like a very efficient sewage treatment plant for the body; it’s where toxic substances are removed and useful ones are recycled. Blood from the rest of the body passes through this vein to be processed by the liver cells that surround the vein.

Liver Central

What would you see if you peered inside a human small intestine? Here’s a glimpse at its structure, revealing a community of cells with different functions.

A Glimpse into the Intestine

This may look like a giant supernova in space, but it’s actually a microscopic image of cytoskeletal proteins and DNA in the metaphase stage of cell division. You can see two of the main proteins that make up the cell’s cytoskeleton – actin (in red and orange) and tubulin (in white) – as well as the cell’s DNA packed into its chromosomes (in blue).

A Snapshot of Cell Division 

This colorful image of a fruit fly eye highlights the organization of the fly’s visual system. Eyes like these are great at sensing motion but are not as good as human eyes at providing a detailed view of the world.&nbsp;

Eye on the Fly

Like Native American dreamcatchers made of strings stretched across a rigid frame, the cells in our body contain various ropelike structural elements – like these intermediate filaments of a protein called vimentin – that protect, support, and shape our cells.

Vimentin Dreamcatcher

It may surprise you to learn that cells have skeletons, too – a cytoskeleton. However, a cell’s skeleton is not made of bones but of a specific set of proteins that form filaments and fibers within the cell to give it structure. In this image, you can see two of the main types of proteins that compose a cytoskeleton: actin and tubulin.

Cytoskeleton Crew

Spiders move around their webs by walking along the strands of silk. Similarly, cells use a network of molecular “highways” called microtubules to move cellular and molecular components around. This image shows a “map” of these highways in several adjacent cells.

Cellular Spiderwebs 

It may look here as if aliens are landing. But this fleet isn’t extraterrestrial. These are desmids – microscopic, single-celled green algae that live in aquatic environments like swamps.

Desmid Delegation

Fun fact: The hexagon is the most common shape in nature. The hexagons in this image are in the eye of a dragonfly. Each hexagonal rod, called an ommatidium, contains major structures that have analogues/counterparts in our own eyes.

Eye of the Dragonfly

Imagine if your foot looked like this. Shoe shopping would be a nightmare! But this is the foot of a diving beetle, and fortunately diving beetles don’t need shoes, as their legs and feet are perfectly designed for both swimming and mating.

Foot of the Diver

The faceoff between these two fiery-looking groups of chromosomes represents a key part of cell division – the process that cells undergo when they divide to make more cells. These images show a stage of cell division called anaphase, in which a cell pulls two sets of its DNA (one set newly copied) to the cell’s opposite ends.

Illuminating Anaphase 

This blazing, writhing orb is the cytoskeleton of a cell. Cells are constantly in flux. The motion in this video is caused by a structural protein called actin, which organizes into rope-like arrangements that help a cell hold its shape and, in some cases, move.

Sunshine on the Cytoskeleton

Take a look inside the bladder of an aquatic bladderwort plant. You can see the single-celled algae, called desmids, that it has consumed. They will be digested to provide the plant with needed nutrients.

Inside a Bladderwort’s Belly

Try not to fall into the gaping maw of this aquatic plant known as a bladderwort. If a small organism touches the trigger hairs on the “trapdoor” shown in this image, a quick flow of water sucks the prey into the plant’s trap.

Open Your Trap

Ever seen legs like these? You’re looking at the legs of a brine shrimp, also known as a sea monkey. But these are not just ordinary legs. As brine shrimp rhythmically beat their legs, they are using these appendages to simultaneously move, eat, and breathe.

Briny Swimmers

Crane flies generally do not eat once they’re adults, but they do drink – and this labrum, or mouthpart, of a crane fly is well adapted to a liquid diet. Although crane flies look like giant mosquitoes, you can ease your mind knowing that they don’t bite.

Labrum Spectrum 

This intricate structure of blue rods and red dots is a cross section through the eye of a damselfly. Insects’ compound eyes are structured very differently than the eyes of humans and other mammals, but there are some similarities in the basic components of the two kinds of eyes.

Inside a Damselfly Eye

This cross section through the flight muscles of a dancer damselfly shows in blue the muscle fibers that the fly uses to flap its wings. You can also see the nerve that stimulates these muscles in red.

Muscles on the Fly

These dung beetles bring home balls of dung for food. The three small males pictured here each have a pair of long horns so they can go head-to-head when competing for females. Because dung beetles feed on manure, they are valuable for cleaning pastures.

Put on Your Dungarees

This cross section through the head of a jumping spider shows off the interior structure of four of its eight eyes. Jumping spiders have the most acute vision of any terrestrial invertebrate. In fact, their ability to perceive detail almost matches that of humans, and they accomplish that feat with eyes that are only a tiny fraction of the size of our eyeball.

Getting Into a Spider’s Head 

This jumping spider appears to be staring at you with four giant eyes, but it actually has eight eyes around the top of its cephalothorax (head and upper body). While the largest pair of eyes provides very acute color vision, the three smaller pairs of eyes offer a less detailed, monochromatic, panoramic view.

Jumping Spider Focus 

These blue branches are the microtubules of developing neurons from a sea snail in the genus Aplysia. And the purple “fringe” on their ends are growth cones, which allow the neurons to grow in the proper direction toward their targets throughout the body.

Purple is the Color of Progress

This is a image of a cell that is nearing the end of the multistep cell division process. At this point, the parent cell is about to pinch off its cell membrane (at the center of the image), which will result in two daughter cells.

Long Division

This cell cluster may look jumbled, but it is well organized. Called a glomerulus, it’s a cluster of cells from a kidney; it filters and processes blood to maintain proper levels of water, salt, and minerals. It also removes toxins from the blood so they can be expelled in urine.

Blue-Green Glomerulus 

These barnacle legs look like a brush that might be used by a chimney sweep. Often attached to ships, barnacles use their hairy legs to comb through the water to collect organisms, mostly microscopic invertebrates, to eat.

Brush Me, Barnacle

This looks like it could be a cartoon rendering of deer antlers, but it’s actually the growing tip of red algae, an organism that thrives in salt water near coral reefs or in tide pools.

Here’s a Tip for You

In this image, red is the color of absorption. The red cells in this image are enterocytes, which line the walls of your small intestine and are responsible for absorbing nutrients from the food you eat, thanks to projections in the intestinal wall called villi.

All About Absorption

Skin is pretty amazing. It is our largest organ, accounting for about 15% of our body weight. It protects our insides from the outside world, cools us off, and keeps us warm. To keep it intact, the body uses a complex network of support.

Skin Networks

There is an undeniable connection between a pregnant individual and their fetus, an unseen bond that is difficult for anyone who has not experienced it to understand. And here we can see that there is also a physical bond with a fetus that develops in the placenta during pregnancy.

The Tapestry of Life

Even cellular components need good roads to travel along. This image shows key components of the cytoskeletal road map labeled in red, blue, and green.

Cytoskeletal Highways 

This cross section through several mouse testes shows how sperm are made and maintained.

Tending the Testes 

This is neither an award nor a sculpture. It’s the fruiting body of a slime mold – a structure that helps the slime mold reproduce and spread. Fruiting bodies contain spores that are released into the environment and have the potential to start a new slime mold colony of their own.

Award-Winning Slime

How does a breast release milk for a baby to drink? The cells you see in this image wrap around groups of milk-producing cells in the breast. These cells can contract to force milk into the network of ducts that collect and eventually funnel milk to the nipple.

Cell Squeezers

Researchers create organoids, like this breast organoid, so they can study the structure and function of organs and tissues in a lab.

Ovation for Organoids

Look inside the foot of a gecko and you’ll see a structure that’s perfect for grasping almost any surface. Geckos’ ability to move in any direction in an instant gives them a leg up when they’re hunting insects or escaping from predators.

Grasp of a Gecko

Most people don’t spend a lot of time thinking about how a fungus reproduces, let alone about what the process might look like. But here you can see a network of soil fungus, with a reproductive spore at the center of the image.

Spore Spotting

This haunting image of a newly discovered organ offers unique insight into how fish protect their gills. This organ harbors immune cells that help fight infection and clear debris.

A Specter in the Gills

To figure out how our brains form as we grow, researchers study what is happening in each individual cell. Here, you can see several neurons from a mouse during the process of development.

Neurons in Development 

Stem cells can specialize, or differentiate, into many different types of cells. This is a snapshot of a group of marmoset embryonic stem cells in the process of differentiating into neurons.

A Multitude of Possibilities

Just like neurons in a brain, neurons growing in a petri dish will reach out to connect with each other. This network of green and purple starbursts shows a group of nerve cells isolated from an embryonic rat.

Early Nerves in the Spine

Every process has a beginning and end, but sometimes the middle segment is the most interesting. This is an image of a neural stem cell in the midst of the process of differentiating into a neuron.

Mid-Transformation

During development, cells move around all the time, but we rarely get a good look at such movement. This video tracks the migration of cells in a developing zebrafish – some of which will be part of the sensory system through which it perceives water movement and some of which will form the dark stripes on its skin.

Migration While Developing

In this zebrafish liver, the blood vessels glitter in gold and the bile ducts gleam in neon blue. This image highlights the close relationship between the circulatory system and the cells of the liver.

Blood and Bile

We rarely see the cells that help defend us from the microorganisms and debris that can cause sickness. Visible as white spots in the interior of these intestinal villi, however, are immune cells called macrophages, which do just that. Macrophages engulf microorganisms like bacteria and viruses that can cause illness and also help clean up microscopic debris that, if left unchecked, could accumulate and cause damage.

Intestinal Fortitude

We mainly curse mucus as we are blowing it from our noses or coughing it up from our lungs because of some allergy or ailment. However, mucus plays a key role in defending our bodies from illness. This is true of both our respiratory and our digestive systems. The tissue shown here is from the small intestine of a mouse; the blue spots are goblet cells, which produce protective mucus.

A Collage of Defense 

These overlapping fibers form the dental enamel in the tooth of a mouse. The enamel is the outermost part of a tooth and is what gives a tooth its structure and strength.

Chew on This

This colorful collage is a group of kidney cells from a mouse with a festive-sounding name. Researchers genetically engineered the so-called confetti mouse so it has cells that fluoresce in combinations of red, blue, yellow, or green depending on the protein each cell produces.

Confetti in a Mouse

No, you’re not experiencing double vision. Unlike most other cells in the body, this human liver cell – also known as a hepatocyte – has two nuclei, seen here in blue. Hepatocytes are the most numerous cells in the liver and are essential for its proper function.

Double DNA in the Liver

The small bumps you can see on the tip of your tongue when you look at your tongue in the mirror are taste papillae. And at the back of your tongue are large taste papillae, with deep trenches lined with hundreds of taste buds. Both the small taste buds on the tip of our tongue and the taste buds lining the large papillae at the back of our tongue allow us to perceive the taste of our food. &nbsp;

A Canyon for Taste

Teamwork makes the dream work, even in nature. When different species work together for their mutual benefit, it is called symbiosis (or mutualism) — a process that is essential for the health of ecosystems.

Symbiosis in Saliva

The little green dots in this image are particles of a coronavirus known as SARS-CoV-2 – the virus that causes the disease COVID-19. These viral particles (also known as virions) are on the surface of a cell that shows signs of being near death.

COVID-19 Up Close

The green wormlike structures covering the blue cell in this image are individual Ebola virus particles. This is the virus that causes Ebola virus disease (EVD), also known as Ebola hemorrhagic fever; without treatment, it can be fatal to more than half of those infected.

Examining Ebola

This is a mugshot of a killer. The little yellow dots are HIV (human immunodeficiency virus) particles, also called virions. HIV is the virus that causes AIDS (acquired immunodeficiency syndrome), an extremely deadly viral disease that is now manageable through medical treatment.

HIV Virions

This golden mass is a cancerous tumor in a zebrafish. Images like these can help researchers study the progression and spread of tumors.

Cancer in a Pisces

This roughed-up red blood cell is infected with plasmodium – the parasite that causes malaria. These parasites invade and reproduce inside red blood cells and cells of the liver, causing fever, fatigue, and other symptoms that can lead to severe illness and even death.

Malign Malaria

MRSA (pronounced MUR-suh), seen here as purple spheres, is the abbreviation for methicillin-resistant Staphylococcus aureus, an antibiotic-resistant bacterium that can cause a severe infection in humans.

MRSA Management

When you feel sick, you probably feel like lying down to rest rather than running around the room. But that’s not the case for the microbes that make you sick. In this video, you can see more and more cells turn purple as they are infected with rotavirus – a virus that makes us sick. The fast green flashes of light show communication between cells.

Rotavirus on the Move

Scientific research is our best defense against emerging threats. Ongoing research about how SARS-CoV-2, the virus that causes COVID-19, impacts the cells it infects is helping to identify new pathways for developing treatments.

Coronavirus on the Rampage

These little yellow buggers are Coxiella burnetii bacteria infecting the interior of a cell. Coxiella burnetii is the bacterium that causes Q fever, which mainly infects farm animals like cows, sheep, and goats.

Q is for Coxiella Burnetii

This 3D reconstruction of a melanoma cell provides scientists with valuable insights into the structure, function, and spread of this deadly cancer.

Melanoma in 3D

The small yellow rods seen resting on these purple blades are Yersinia pestis bacteria – the cause of bubonic plague. This bacterial infection is mainly spread to humans by fleas but can also be spread through direct contact with an infected person or through respiratory droplets exhaled by an infected person.

Plague on Purple

These little red salmonella bacteria are one of the main causes of food poisoning. If you ingest enough of these bacteria, they can infect your intestinal tract and lead to serious illness.

Red Alert

Try to pick out which of these human red blood cells is not like the others. You got it – the topmost cell in this image exhibits the characteristic sickle shape of red blood cells in individuals affected by sickle cell disease.

Cutting Out Sickle Cells

This red blood cell is trapped in the traumatized muscle tissue of a soldier receiving treatment for severe muscle damage.

Trauma Team

These two Klebsiella pneumoniae bacteria are close to being nipped in the bud, as the tendrils of a neutrophil close in to engulf and digest them. However, if these bacteria got into your lungs (or a wound) in great enough numbers, they could cause a serious, antibiotic-resistant infection.

Pneumonia Being Nipped in the Bud

This image shows several dozen Neisseria gonorrhoeae bacteria – the cause of a painful and life-threatening disease called gonorrhea. Gonorrhea is a sexually transmitted disease, but it can also be transmitted to a baby during childbirth, as the infant passes through the birth canal.

Fire Down Below

This colorful “explosion” is a choroidal neovascular (CNV) complex in the retina of a rat. A CNV complex is an abnormal growth of blood vessels under the retina after an injury.

Unwelcome Vessels in the Eye

This is a skin wound on a mouse, surrounded by immune cells (in blue) and beneficial bacteria that live on the skin (in green). During wound healing, immune cells and bacteria work together to prevent infection.

A Surprising Collaboration

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 support cell.

Highways for HIV

The colorful threads in this image are muscle fibers. This spotted rainbow illustrates a potential gene therapy approach to treating Duchenne muscular dystrophy (DMD) – a rare, debilitating, and fatal disease that weakens an individual’s muscles.

A Fix for Muscle Mutations

These worm larvae may look pretty, but you should keep your distance. Once they get a little more mature, they could infect you and make you sick.

Dangerous Potential

Pioneering research has shown that the immune system is quite good at fighting cancer if it knows what to look for. This image shows a patient’s immune cells (in red) attacking a cancer cell (in white) during treatment.

Cancer Under Siege

The purple blotches you see in this image are lung cancer cells from a genetically modified mouse. These cancer cells developed due to a mutation in a gene called KRAS – which is also a driver of multiple cancers in humans.

KRAS Cancer

The light blue rods in this image are particles of respiratory syncytial virus (RSV); the tiny gold specks covering them are antibodies. These antibodies are useful not only because they allow researchers to visualize the virus with fluorescent tagging, but also because they can be used to target the virus in a treatment for RSV.

Attacking RSV

These yellow spheres are Streptococcus pyogenese bacteria bound to a human neutrophil – a key part of the immune system. Streptococcus pyogenese is the bacterium that causes strep throat in humans.

Visualizing a Sore Throat

The rainbow-hued splotches that you see here signal the presence of precancerous tissue in the pancreas of a mouse. An image like this offers insights to researchers who study the development of pancreatic cancer.

Cautionary Colors in the Pancreas

The green specks in this image are particles of the Middle East respiratory syndrome (MERS) coronavirus; the red in the background is a kidney cell in culture. This is a rare virus from the same family as SARS-CoV-2, which causes COVID-19.

A Rare Glimpse of MERS

These teal corkscrews are Treponema pallidum – the bacterium that causes syphilis. Syphilis is a sexually transmitted infection, but if left untreated it can affect other areas of the body, including the nervous system, where it can cause severe neurological damage.

Cursed Corkscrews

It’s widely known that malaria is spread by mosquitoes. But how often do you get to see the mechanics of that process up close? Here, you can see red malaria parasites in a single drop of mosquito saliva.

Malaria Migration

These pink and purple ovals may look like colorful hard candies, but you should avoid eating them. They are enteropathogenic Escherichia coli – bacteria that can cause serious illness and even death.

Intestinal Invaders

This knobby sphere is a critical part of the immune system; it’s called a B cell, or B lymphocyte. These cells are responsible for producing antibodies that bind to pathogens, blocking their entry into cells or labeling them for destruction by other immune system components, like T cells.

B Ready

The tendrils that extend from so-called killer T cells like the one in this image help them latch onto and destroy infected or cancerous cells in the body.

 I Pity the Fool Who Infects Me!

This seemingly red-hot macrophage is one of the key components of the human immune system. These cells identify, engulf, and destroy pathogens and allergens that enter our bodies and clean up cellular detritus to keep it from accumulating in our bodies.

Fiery Defender

Helper T cells like this one are arguably among the most important components of the immune system. They help activate many other cells and processes in the immune system, increasing its overall efficiency.

Lending a Helping Cell

Researchers have figured out how to use tiny synthetic polymers called nanoparticles to target and fight cancer cells. This image shows the immune system cells that are mobilized by nanoparticles to initiate the fight against cancer cells.

Fighting Cancer at the Nano Level

The human immune system usually works wonders, protecting us from all sorts of diseases. However, if the immune system goes into overdrive, it can become even more dangerous than the diseases it protects us against. The cells shown here in red are regulators of the immune system that try to prevent that from happening.

Regulators of Immunity

This colorful tapestry is a section of heart tissue from a zebrafish. The pink clusters are T cells, immune cells that help defend against disease.

Protecting the Heart

The feather-like structures at the top of this image are the gills of a zebrafish. The tissue below the gills is amphibranchial lymphoid tissue, a newly discovered structure that is enriched with immune cells.

Guarding the Gills

Love them or hate them, snakes are biologically fascinating. This image shows the skeleton of a corn snake. Its flexible spine and jaws allow it to eat animals like mice and rats that you would never think could fit in its mouth.

Skeleton of a Snake

These dark blue tubes splattered with red and green are fruit fly muscles. This image shows where the nerves and the muscles meet in the larva of a fly.

Where Nerve Meets Muscle

This is a rare peek at how cartilage transforms into bone. In this image, you can see cartilage (in purple and white), blood vessels and cells (in yellow), and other specialized cells that create space for the structures within bones (in red).

Inside Developing Bones

This burst of red, green, and yellow strands and teal dots is a group of mouse muscle cells that has been cultured in a petri dish. Unlike most cells in the body, these cells have multiple nuclei, seen here in teal.

Muscles in a Dish

This “blossom” is made of overlapping images of a growth plate from the bone of a two-week-old mouse.

Growth Plate in Bloom

This image shows off some of what’s inside a zebrafish. You can see many of the zebrafish’s structures, including its bones and scales and parts of its lymphatic system.

Inside a Zebrafish

Pyramidal neurons, shown in green in this image, account for about two-thirds of all neurons in a mammal’s cerebral cortex, making them important for many cognitive processes. The purple cells produce an important neurotransmitter involved in communication among brain cells – including pyramidal neurons.

ChitChaT with Pyramids

With modern tools, we can see the connections formed between different types of neurons throughout the brain. Although their cell bodies may originate in one place, neurons can communicate with other neurons located elsewhere in the brain using their long axons, which look a little like pathways through the brain. This is a slice from front to back through the brain of a mouse; neurons containing an enzyme called choline acetyltransferase (ChAT) are labeled in purple, and pyramidal neurons are labeled in green.

Explore Collection