Scientific Illustration

biomedicalephemera:

Internal organs of the Chicken

kaylavictoria-artthen:

Gouache

2005

kaylavictoria-artthen:

Gouache

2005

animal-anatomy:

Anatomy of Sirenian from http://www.xavier.edu/manateeresearch/Anatomy-and-Physiology.cfm

ninjies:

a while ago i mentioned i had some anatomical drawings and some people requested them but i forgot to upload them until now!

- DOWNLOAD HERE: http://www.mediafire.com/?o1tdax14yrar4hr

included are roughly 100 anatomical drawings, all of them 300 DPI. someone on /ic/ posted these a couple years ago so i take no credit for acquiring or scanning them, only sharing them.

these are really useful for artists studying anatomy or medical buffs looking for cool stuff to look at. enjoy!

biomedicalephemera:

Sweat glands in the human epidermis:

Diagrammatically represented (top)
Isolated vertical cross-section (Right)
Isolated horizontal cross-section (left)

Staying cool this ridiculous summer, fellow North Americans? Even if you’re hot and miserable and sweaty, your body knows how to keep its organs at the optimal temperature - that’s why you sweat in the heat in the first place!

Unlike other mammals that sweat for thermoregulation (such as oxen and horses), humans largely sweat from their eccrine sweat glands, which are not directly connected to hair follicles. Eccrine sweat glands secrete mostly water, with a few electrolytes (mostly NaCl, which is why sweat tastes salty). The amount we sweat is regulated by the hypothalamus and the contraction of cells surrounding the eccrine glands, and is influenced by hormone release and internal body temperature.

The water secreted by the eccrine sweat glands utilizes a process called evaporative cooling to reduce the surface temperature of the skin, which in turn reduces the temperature of the blood flowing through the expanded arterioles near the skin surface, and that blood flows through the body and keeps the organs and muscles at a relatively constant temperature. Sweat glands are coil-shaped, with a bulbous sac at the bottom that filters blood plasma to produce sweat. When the cells surrounding the sac and coil are triggered, they contract, pushing that sweat to the surface of the skin.

We also have apocrine sweat glands (the only functional thermoregulatory glands in horses and other sweaty mammals), but they’re largely restricted to the armpits, areola, and perianal region. Their secretions are not as simple as eccrine sweat glands - they’re typically milky-white and contain hormones and additional components of blood plasma that bacteria *love* to chow down. Those bacteria produce stinky excretions of their own, and that’s what causes smelly armpits!

When you use deodorant, the substance you apply works by breaking down the components excreted by bacteria that cause the smell, and masking any residual stink that can’t be broken down. Antiperspirants function by plugging the openings of the sweat pores, so that sweat can’t escape. This is usually done with small particles of aluminum. Despite misconceptions, blocking the sweat glands does not cause breast cancer, though some people experience adverse effects due to allergies to aluminum or other ingredients.

Images:

Top: Anatomy, Descriptive and Applied. Henry Gray et al, 1910.
Bottom: Diseases of the skin; a text-book for students and practitioners. J.M.H. Macleod, 1920.

myideabox:

1754 engraving of an eviscerated pregnant female

(via kamikazekurt)

(via fuckyeahmedicaldiagrams)

biomedicalephemera:

Internal Anatomy of the Grass Frog [Genus Litoria]

As different as frogs are from you and I, you can clearly see how similar vertebrates are to each other when you dissect one. One heart, two lungs, a stomach, liver, spleen, gall bladder, intestines, kidneys, bladder, and gonads are visible in this particular dissection, as well as the extraordinarily strong leg muscles.

Brehms Tierleben, Bd. 1. Alfred Brehms, 1911.