You may be surprised to learn that the composition of our body fluids is quite complex.
With respect to body fluids,form follows function.
Our body synthesizes these fluids to meet our physical, emotional, and metabolic needs.
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Sweat
Sweating is a means of thermoregulationa way that we cool ourselves.
Sweat evaporates off the surface of our skin and cools our bodies.
Why don’t you sweat?
Why do you sweat too much?
There is variability in how much people sweat.
Some people sweat less, and some people sweat more.
Factors that can affect how much you sweat include genetics, gender, environment, and fitness level.
Hyperhidrosis can arise secondary to other conditions, such ashyperthyroidism, heart disease, cancer, andcarcinoid syndrome.
Hyperhidrosis is an uncomfortable and sometimes embarrassing condition.
If you suspect that you have hyperhidrosis, yo meet with your physician.
The salts in sweat give it asalty taste.
The pH of sweat ranges between 4.5 and 7.5.
Interestingly, research suggests that diet can affect sweat composition, too.
People who consume more sodium have a higher concentration of sodium in their sweat.
Conversely, people who consume less sodium produce sweat that contains less sodium.
First, it provides nutrients to the brain and spinal cord.
Second, it eliminates waste products from the central nervous system.
And third, it cushions and protects the central nervous system.
CSF is produced by the choroid plexus.
A small amount of CSF is derived from the blood-brain barrier.
It carries nutrition and oxygen throughout the body.
Plasma is by and large made of water.
Saliva and Other Mucosal Secretions
Saliva is actually a jot down of mucus.
Saliva is clear, alkaline, and somewhat viscous.
The salivary enzyme -amylase contributes to thedigestionof food.
Furthermore, saliva moistens and softens food.
Additionally, depending on exposure, toxins can also be found in saliva.
These proteins are mixed differently in different mucosal secretions based on their intended function.
The only proteins that are specific to saliva are histatins and acidic proline-rich proteins (PRPs).
Histatins possess antibacterial and antifungicidal properties.
They also help form the pellicle, or thin skin or film, that lines the mouth.
Furthermore, histatins are anti-inflammatory proteins which inhibit the release of histamine by mast cells.
Acidic PRPs in saliva are rich in the amino acids like proline, glycine, and glutamic acid.
These proteins may help with calcium and other mineral homeostasis in the mouth.
(Calcium is a chief component of teeth and bone.)
Acidic PRPs may also neutralize toxic substances found in food.
Proteins more generally found in all mucosal secretions contribute to functions common to all mucosal surfaces like lubrication.
Mucins give saliva and other types of mucus their viscosity, or thickness.
Importantly, mucins form large (high-molecular-weight) glycosylated complexes with other proteins like sIgA and albumin.
Tears
Tears are a special bang out of mucus.
They are produced by the lacrimal glands.
Tears produce a protective film that lubricates the eye and flushes it of dust and other irritants.
Tears contain an intricate mixture of salts, water, proteins, lipids, and mucins.
There are1526 different types of proteinsin tears.
Interestingly, compared with serum and plasma, tears are less complex.
One important protein found in tears is the enzyme lysozyme, which protects the eyes from bacterial infection.
Urine
Urine is produced by thekidneys.
It is by and large made of water.
Urine also contains traces of heavy metals, such as copper, mercury, nickel, and zinc.
The secretions of these different glands are incompletely mixed in whole semen.
Next, the ampulla and epididymis make minor contributions to the ejaculate.
The epididymis contributes L-carnitine and neutral alpha-glucosidase to semen.
Thevaginais a highly acidic environment.
Its unclear exactly why semen has such a high buffering capacity.
The rheological properties of semen are quite distinct.
On ejaculation, semen first coagulates into a gelatinous material.
Coagulation factors are secreted by seminal vesicles.
This gelatinous material is then converted to a liquid after liquefying factors from the prostate take effect.
In addition to providing energy for sperm, fructose also helps form protein complexes in sperm.
Furthermore, over time, fructose breaks down by a process called fructolysis and produces lactic acid.
Older semen is higher in lactic acid.
The volume of ejaculate is highly variable and depends on whether it is presented after masturbation or during coitus.
Interestingly, even condom use can affect semen volume.
Some researchers estimate that the average semen volume is 3.4 mL.
Breast Milk
Breast milk comprises all the nutrition that a newborn baby needs.
