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Blood is not a good source of water. 1 liter of blood contains about 800 mL of water, 170 grams of protein and 2 grams of sodium (calculated from the composition of lamb blood). When metabolized, 170 grams of protein yields the amount of urea that requires 1,360 mL of water to be excreted in urine (calculated from here); 2 grams of sodium requires about ...


19

The red colour of blood isn't actually to do with food at all. The primary purpose of the blood is to carry oxygen to all the cells that require it to release energy. Red Blood Cells are filled with an iron containing pigment called haemoglobin. When it has oxygen bonded to it, haemoglobin has a bright red colour - it is this that gives blood its red ...


19

You can drink blood of course to a minimalistic amount (eg- a few teaspoons ) and also if blood is free from pathogens. But it should always be in very small amounts and from suitable donor. Here's why The strange fact is, blood, when drank, is toxic. When confined to places where blood is supposed to be — such as the heart, vessels, and so on — it is ...


18

Mucous-producing cells at the neck of the gastric pits create a layer of protective mucous covering the stomach lining. This mucous layer includes bicarbonate ions which act as a chemical barrier against the protons in gastric juice. See here for some evidence. The stomach lining stays protected because the mucous layer is continuously replenished.


18

I wouldn't say that a human is "likely" to get sick by drinking from a puddle, I'd say "at some risk". It isn't desperately dangerous, although don't take that as a recommendation. There are many infections you can get from water (bacterial, viral, amoebal, and I presume fungal). You don't want to risk them, but probably won't actually encounter them in that ...


17

One of the most common toxins in mouldy food/bread is aflatoxin. The exposure to high amount of aflatoxin can lead to acute aflatoxicosis with fulminant hepatic failure and even death. While mild exposure to aflatoxin could be asymptomatic, it is better not to take a chance considering possible complications (citation from the link above): Aflatoxins ...


17

EDIT: Thanks a lot to @abukaj for pointing out the mistake in my answer (and to @paracetamol for asking such a beautiful question). I am rewriting my answer to incorporate the (hopefully) correct background knowledge this time. NEW ANSWER: As @paracetamol and @AlanBoyd (in their answer) pointed out the lack of credible support for the claim that infants ...


16

No, you cannot live off of semen. A source from Columbia.edu: A typical ejaculation fills up about one teaspoon; the actual amount is determined by a man's age (younger men usually make more semen), when he last ejaculated, and how long he's aroused before ejaculating, among other factors. Contrary to what you've heard, semen is not loaded with calories. ...


16

I'm sure it varies wildly based on the animal and what they're eating. In general, if in the course of an animal's natural feeding process it picks up a little dirt, it has evolved to cope with that. Animal's behaviors and guts have evolved to fit their food source and lifestyle. For a behavioral example, seals will eat rough rocks to help breakdown bones ...


13

The blood pH is tightly controlled since variations are quite dangerous for us. Under normal circumstances the pH is 7.4 (with a normal range between 7.35 and 7.45). Below that we are talking about acidosis, above it about alkalosis. If the blood pH goes about 7.8 or below 6.8, death will occur. This pH is maintained by the Bicarbonate-buffering system, for ...


12

The hoatzin has a digestive system that makes use of bacterial fermentation. Many other birds also consume grass, e.g. ostriches, ducks and geese. There's also a large body of literature on how birds can digest cellulose.


11

There are two types of food poisoning: Alimentary intoxication This is the case when you consume food which is contaminated with some toxins, and those are responsible for development of the poisoning symptoms. The source organisms of these toxins might not be present anymore (killed by heating during cooking, for example). In this case there is no massive ...


10

During putrefaction of animal tissue, lysine is decarboxylated into cadaverine and arginine is decarboxylated into putrescine. These compounds are deemed to be toxic. A serving of meat contains 8 g of protein, corresponding to 640 mg lysine and a little bit less of arginine. Let's go straight and say that a spoiled meat serving contains 640 mg cadaverine ...


10

Trans fatty acids are digestible, but they cause an increase in LDL and a decrease in HDL, which is the leading mechanism for atherosclerosis. So, they increase the risk of a cardiac infarct. LDL means Low Density Lipoprotein, it's one of the 5 major lipoprotein groups. Lipoproteins carries the fatty acids and cholesterol which were absorbed from ...


10

First, there are two different isomers of the lactic acid, the L(+)- and the D(-)-form. Both differ in the position of the OH-group in the molecule: Both turn polarized light in different ways, the D(-) to the left and the L(+) to the right. The physiological form of lactic acid for the human body is the L(+) form, which is taken up in the gut and then ...


10

Satiety is complex, and there are several kinds of satiety, all of which come into play in different circumstances. Things that decrease or halt our eating are called satiety signals. Different satiety signals are put out by different substances (carbohydrates, fats and proteins) as well as by things like gut stretching and other signals. There is also a ...


10

Dizziness after eating, which can lead to falls and passing out, is called postprandial hypotension, and as the heart is indeed responsible for responding to hypotension by increasing it's rate - which can be seen in any number of clinical scenarios from blood loss to standing up too suddenly - failure to do so, for any reason including heart disease, can ...


10

Yes, they do. For a look at survival of Lactobacillus and other bacterial species after multiple freeze/thaw cycles, check out Harrison 1955 (below). The awesome hand-drawn graphs show that many bacteria survive after being frozen for 11 weeks. There's also a figure on the following page showing that many bacteria also survive after multiple freeze-thaw ...


10

Here is a specific account of a person surviving at sea drinking turtle blood, while eating some fish and drinking some rain water. Several peoples have a habit of drinking raw animal blood, at least for ritual purposes; here is a recent account. They probably drink more than a few spoons full so that the Lifescience article quoted by Ishi appears alarmist.


9

The bowel movements are influenced by a lot of factors. For example, when you eat a meal it induces a movement in your large intestines, to defecate and clear up space for new food. Also, there is MMC, migrating motor complex, which is responsible for the bowel movements when you are fasting. It causes a flushing effect, which prevents bacteria to ...


9

Quite a bit can be absorbed through the mouth. Most commonly, starches are broken down to maltose (two glucose molecules formed by a condensation reaction) and are easily absorbed by the bloodstream. A lot of other factors balance into this, ie pH, lipid solubility, and molecular weight. Generally, if a substance is easily dissolved in saliva, it can be ...


9

Wow! What an interesting question! I did a bit of searching around, and here's what I found. It looks like the baby kangaroos, or joeys, do in fact produce excrement while in their mothers pouch. The mother kangaroo uses her tongue to clean her joey and her pouch. I found this information in a couple of differently places by doing a google search for "...


9

Short answer Various inhalants, most notably organic solvents including those used in paint and glue suppress appetite. Background From the Division of Alcohol and Drug Abuse I learned the following: Initial effects [of various inhalants] include nausea [...], and a loss of appetite. And the Humanitarian Irin News reports the following on Nepali ...


8

I don't know about ruminants, but baby rabbits (and presumably other lagomorphs) apparently acquire the necessary intestinal flora by consuming their mother's cecotropes.[1] [1] Johnson-Delaney, C.A. (2006), "Anatomy and Physiology of the Rabbit and Rodent Gastrointestinal System" (PDF)


8

I would not expect this to be any different than other animals - they get the flora from the environment. Key components of the environment for newborns are: Birth canal Den / living quarters Skin / fur of mother, especially near the teats Diet Feces of family members (animals sniff this and aren't so clean)


8

The pressure that you apply when you push during a bowel movement derives from an increase in the pressure of the abdomino-pelvic cavity. You generate this pressure by closing the glottis (the opening to the lungs) and contracting the anteriolateral abdominal muscles (i.e., the external oblique, internal oblique, and transversus abdominus). This reduces ...


8

The function of bile produced by the liver and concentrated in the gall bladder is to aid in fat digestion. Bile acts as an emulsifier to allow the fat to be packaged into small droplets, micelles. The breakdown of fats into small micelles greatly increases the surface area for lipases produced by the pancreas have to act on. These are then absorbed ...


8

How are diabetes and obesity connected in light of low lipase activity? Short answer: There's more than one type of diabetes. (And to complicate things, there's also more than one type of lipase. It's unclear from the question which type were mentioned in what you read.) Diabetes mellitus is usually divided into Type 1 (insulin-deficient) and Type 2 (...


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