Body Fluids pt. 3
A continued investigation of our wet, drippy, sticky bits. Slosh on.
Find pt. 1 here, and pt 2 here

Vomit
Salivary glands begin producing more saliva right before we throw ups as an alkaline buffer to the stomach acid about to pass through the mouth
Sympathetic nervous system raises the heart rate which makes you sweat as a form of temperature regulation from the sudden heat created by the process of vomiting
The vomit response is created in the brainstem
Apparently snakes can vomit too. Check out this video of a python eating an antelope them immediately puking it up. Cute.

Endolymph/
Perilymph
Endolymph and perilymph are two fluids a fluid in your ear that are part of the vestibular system (sensory system that communicates head position and orientation to the brain)
Vibrational waves through these fluids are detected by ear receptors and translated by your brain as sound
Endolymph is what causes motion sickness…when there are jerky or continuously disruptive movements in the endoymph, the brain has a hard time figuring out why the ear fluids are moving but the body is still. This confusion results in the symptoms of motion sickness (nausea, vomiting, headache, drowsiness)

Stomach Acid (hydrochloric acid)
Has a pH ranging from 1-5-3.5 (aka super acidic)
Provides the chemical breakdown of food, assisted by the mechanical “churning” of the layers of stomach muscle
Stomach acid would literally burn us from the inside out if contents weren’t immediately neutralized with bile as they empty from the stomach to small intestine
Stomach acid kills microbes in food
Secreted by parietal cells that line the inner stomach. These cells also produce “intrinsic factor” which is needed in the absorption of vitamin B12
Mucus

Slippery fluid that lines cavities exposed to the exterior (nose, mouth, throat, lungs, G.I. tract and much of the urinary tract)
The cells that make up our mucus membranes are adhered very tightly to one another, creating a selective barrier, and uses antibodies in mucus to trap and incapacitate foreign invaders
The active ingredient in mucus is called “mucin”, which in some instances will bind to bacterium and stimulate the use of a tail (called a “flagellum”). That tail makes the bacteria move around more and therefore less likely to accumulate)

Phlegm
(A.K.A.“sputum” once it’s coughed up), phlegm is a mixture of saliva and mucus coughed up from your respiratory tract. Mucus is a normal protective layering that we need always, while phlegm is more a sign of inflammation and carrier of debris
Ancient greek philosophers subscribed to the idea of “the four bodily humors”, which attempted to explain human function in terms of a necessary balance between 4 substances: Black bile, Yellow bile, Blood and Phlegm. Associated with water, phlegm includes the clear plasma components of the self: mucus, saliva, plasma, lymph, serous and interstitial fluid. Physically the phlegm humor is associated with coolness, lubrication, nourishment and protection. Emotionally, its “subtle vapors” affect passivity and lethargy on one end, and sensitivity and sentimentality on the other end.
There are really only two ways to get rid of excessive phlegm…spit or swallow

Synovial Fluid
Found in every moveable joint in the body
Has an thick, stringy “egg like consistency” and is named as such, from syn- (greek for “with”) and -ova (latin for “egg”)
The membrane around a synovial cavity has folded tissue that secretes synovial fluid when it’s moved or compressed. This is why joint mobility is so lubricating...movement of the joint squeezes the synovial membrane and stimulates the release of fluid

Serous Fluid
Lives in peripleural, pericardium and perotineal cavities. (around the lungs, the heart and the abdominal organs)
Serves as a layer of protection around organs and keeps the outer surface of the organs (visceral layer) from rubbing against or sticking to the inner layer of muscle(parietal layer)
Creates space around organs to account for potential changes in pressure
The esophogus is the only organ of the digestive system not surrounded by the perotineal cavity. There is only one lining of tissue surrounding the esophogus, and it’s called the “adventitia”, which is more of a rigidly fixed connective tissue compared to serousa.

Sweat
There are 3 to 4 million sweat glands on a human body
2 types of sweat glands:
1) Eccrine sweat glands
Empty through pores on your skin
Most numerous on the forehead, palms and soles
Used mostly for thermal regulation (like when it’s hot our or when you exercise)
Active immediately after birth
2) Apocrine sweat glands
Empty through hair follicles
Used mostly in “emotional sweat” or “cold sweat” (like when you’re nervous and get pit stains)
Don’t start to function until puberty
Secretions more viscous and smellier than eccrine glands
The body’s thermostat is a structure in the brain called the hypothalamus. It has thermal regulators that can sense the body’s temperature through receptors in both the skin and the core. It will compare your current body temperature to a “set point” and initiate the process of sweating when the body’s internal temperature gets too high.

Urine
ON COLOR: Pale straw colored urine is generally regarded as normal, healthy urine. Transparent urine can mean overhydration. Light orange urine can be a sign of excess B vitamins or problems with the liver/bile duct. Milky urine can mean an overabundance of certain minerals or excessive protiens. Melanoma can cause blackish urine, called “melanuria”
ON SMELL: Fresh urine can smell, but stale urine develops more stank as bacteria breakdown urea into ammonia. Furthermore, musty smelling urine can indicate liver disease, while sweet smelling urine can indicate diabetes.
For the last bits of urine flow, women empty using simple gravity, men have to contract the “bulbospongiousus” muscle several times to empty all the way
When someone has difficulty urinating in public restrooms, it’s called “paruresis”. When someone is aroused by urine, it’s called “urolagnia”
Women in ancient Rome would drink turpentine to make their urine smell like roses
References:
"The Four Humors" Osborn, D.K. http://www.greekmedicine.net/b_p/Four_Humors.html
"Review of the Tribological Characteristics of Synovial Fluid" Prekasan, D., Saju, K.K. https://www.sciencedirect.com/science/article/pii/S2212017316305898
"All About That Mucus: How it Keeps Us Healthy" Zheng, J. http://sitn.hms.harvard.edu/flash/2018/mucus-keeps-us-healthy/
"What Happens in my Body When I vomit?" Lockey, R. https://www.sciencefocus.com/the-human-body/what-happens-in-my-body-when-i-vomit/
"14 Random Facts about Pee". Hawkins, A. https://www.goodhousekeeping.com/health/a22725/urine-facts/
"10 Colors That Suggest Urine Trouble" LaFee, S. https://www.goodhousekeeping.com/health/a22725/urine-facts/
"You May Be Eating Vomit, and More Bizarre Barf Facts". Langley, L. https://www.nationalgeographic.com/news/2017/03/vomit-throw-up-snakes-pythons-vultures/
“Principles of Human Anatomy” Tortora, G.J., Nielsen, M.T.
"Different Body Fluids: An Overview". Guattnam, N., Singh, S.P., Khinchi, M.P., Nama, N., Jain, S. https://ajprd.com/index.php/journal/article/view/322/282