Who is Paul Langerhans, and how did his islets wind up in your pancreas? Good question. Although lots of body parts take their names from Greek or Latin, more than a few are named after people. How well do you know the folks whose names are all over your body? Let's take a look at a few of these scientists and their anatomical namesakes.

1. Canals of Schlemm

Schlemm's canals are tiny channels in the eye that move aqueous humor, the watery fluid that resides between the lens and the cornea. The canals are named after 19th-century German anatomist Friedrich Schlemm, a University of Berlin professor who also discovered corneal nerves.

An interesting story about Schlemm: according to recent historical research, when Schlemm was a 21-year-old medical student he teamed with a classmate to disinter a recently deceased woman with rickets. Schlemm and his buddy took the corpse back to their lab to study how the disease had affected the woman's bones, but they were eventually caught and had to spend four weeks in jail for the grave robbery.

2. Fallopian tubes

As anyone who's passed a sex ed class might remember, Fallopian tubes are the thin tubes that lead from the ovaries to the uterus in female mammals. They're named after 16th-century Italian anatomist Gabriele Falloppio, who also went by the Latin name Falloppius. Although Falloppio focused on the head in most of his own research, he also did some work with the reproductive tract.

In addition to discovering and describing the tubes that bear his name, he also studied syphilis and gets credit for sponsoring what may have been the first clinical trial of condoms around 1546. Falloppio's contraceptives were made of chemically treated linen that wearers tied on with a ribbon; he wrote that they helped decrease the rate of syphilis transmission.

3. Islets of Langerhans

No, it's not a tiny archipelago off the coast of Newfoundland. The islets of Langerhans are actually the parts of the pancreas that contain endocrine cells. Although they only make up 1 to 2% of the pancreas' mass, they have a lot of important functions, like secreting insulin. The islets are named after Paul Langerhans, a precocious 19th-century German pathologist. Langerhans made his breakthrough discovery at the age of 22 when he described "islands of clear cells" in the pancreas.

4. Langerhans cells

We weren't kidding when we called him precocious. When he was just 21, Langerhans also discovered and described Langerhans cells, a subset of skin cells concerned with immune responses. Although he mistakenly hypothesized that the cells had something to do with the nervous system, Langerhans was the first to isolate them, so they bear his name.

5. Organ of Corti

The tiny organ in mammals' inner ears that contains the hair cells that make hearing possible is named after Italian anatomist Alfonso Giacomo Gaspare Corti, who discovered it in 1851.

6. Cowper's glands

These small exocrine glands—also known as bulbourethral glands—are located at the base of the penis and help optimize conditions for sperm in the urethra during sexual arousal. The Cowper's glands are named after William Cowper, a 17th- and 18th-century British anatomist who made an early description of the glands.

Don't think for a second that an anatomist in Cowper's time had a boring life, either. In 1698, he published the watershed text The Anatomy of the Humane Bodies, which featured dozens of painstaking illustrated plates and quickly turned Cowper into a superstar anatomist. The only problem was that the plates weren't really Cowper's; he had lifted them from an earlier commercial flop by Dutch physician Govard Bidloo and written new copy to go with them. Unfortunately for Bidloo, Cowper didn't acknowledge his Dutch counterpart's contributions, and a bitter feud ensued that lasted for the rest of Cowper's life.

7. Bartholin's glands

Women may not have Cowper's glands, but they do have the homologous Bartholin's glands. These two glands lubricate the vagina in much the same way the Cowper's glands prepare the urethra for sexual activity. Their name comes from Danish anatomist Caspar Bartholin the Younger, who was active in the 17th and 18th centuries and first described the glands.

Discoveries like this must have come naturally to Bartholin. His grandfather, Caspar Bartholin the Elder, published the first description of the olfactory nerve, and his father, Thomas, wrote the first comprehensive study of the human lymphatic system. His uncle Rasmus also has a body part named after him: the major sublingual duct, part of the sublingual salivary glands, is known as the duct of Bartholin.

8., 9. & 10. Bowman's capsule, membrane & glands

Bowman's capsules are cup-shaped structures around the glomerulus of each nephron in a kidney. The capsule helps filter out waste and excess water. Bowman's capsules are named after 19th-century English anatomist and ophthalmologist Sir William Bowman, who identified the structures in 1842 when he was 25 years old.

Not content to rest on his laurels after making one major discovery, Bowman pressed on with his work, and Bowman's membrane—a smooth, thin layer of the eye—also bears his name. Bowman's glands, a set of olfactory glands, are named for him, too. People in high places took notice of Bowman's prodigious research output; Queen Victoria created him a baronetcy in 1884.

11. Eustachian tubes

Everyone's familiar with "popping your ears" to equalize pressure after a flight, but fliers aren't actually popping anything. Instead, they're opening their Eustachian tubes to equalize the pressure between their ears and the atmosphere. These tubes, which also help drain mucus away from the middle ear, are named after 16th-century Italian scientist Bartolomeo Eustachi, also known as Eustachius.

Eustachi discovered all sorts of new information about the structure of the ear, and today he's known as one of the fathers of human anatomy. But he didn't get too much credit in his day. In 1552, Eustachi completed the text Anatomical Engravings, which showed an ahead-of-its-time understanding of the human body. Eustachi didn't dare publish his work, though, for fear of excommunication from the Catholic Church. The manuscript hung around for decades, and eventually reached publication in 1714, when it became a bestseller and illuminated just how much progress Eustachi made.

This post originally appeared in 2009.