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The physiological process of breaking down food into its constituent parts to provide nutrition for the body.

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Is gut bacteria Succinivibrionaceae's low methanogenesis understood well enough for GM of cattle gut bacteria to be considered?

After watching the Periodic Table of Videos episode linked in this question I watched the episode Wallabies and Methane where Sir Poliakoff says (a bit after 02:00):...
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0answers
32 views

What is the process of protease in digestion? [closed]

On a worksheet in my biology class, we have the following question: Complete the following: Pepsin, a type of protease, digests _______ into smaller molecules called _______. This occurs in the ...
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3answers
62 views

Could a mammal convert ingested dissolved CO2 to usable energy?

I'm trying to find out if it's possible that a mammal could orally ingest dissolved CO2 and convert it to energy for body heat, organ function, etc. Unfortunately, most of the scientific sources I've ...
0
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1answer
13 views

Micelles Sticking Together

I have a quick question regarding micelles. I have tried googling the answer but can't seem to find the answer. The question is, during digestion lipids are emulsified into micelles in order to ...
7
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1answer
96 views

Why does flatulence vary in temperature and smell?

Quite simply, why do some farts feel warmer than others? Some feel regular, while others feel like lava. What causes this? If there is no real temperature difference, why do I perceive some to be ...
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0answers
23 views

How cells determine how many enzymes are needed for digestion

How do pancreatic cells, epithelial cells of the stomach and intestinal epithelium cells determine the right amount of enzymes for digesting carbohydrates, proteins, fats? How does the pancreas ...
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1answer
38 views

Apolipoprotein B48 and fat storage

Can chylomicrons formed in the intestine, with apolipoprotein B48, transport lipids to adipose cells for storage?
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1answer
24 views

What is the difference between pseudorumination and coprophily? [closed]

Can someone please explain me difference between these two terms. any help is appreciated.
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37 views

Bird vs Fish Encounter?

Visiting a beach at the ocean, I recently saw a Great Blue Heron dive and catch quite a spiky/large (and colorful! I think it was called a sculpin) crosswise in it's bill. It appeared, potential meal ...
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0answers
29 views

What determines the energy efficiency of our bodies?

Ingested food is broken down into the macronutrient components and then absorbed into the body. They are then used immediately or stored for future use. However, our energy efficiency is very low. So, ...
3
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0answers
32 views

Can the human gut work with other type of gut bacteria?

I was wondering if the human body would be capable of functioning with, say, cellulolytic bacteria in their gut (instead of or in addition of their current bacteria), like that of ruminants and if ...
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0answers
19 views

Can humans derive any nutrition from eating the bones of animals?

Bones contain many nutrients like Calcium and phosphorus. And I'd take a guess that some kind of bones like bones of a chicken(hollow) aren't dense enough to be much of a problem during digestion. ...
2
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1answer
82 views

Why does drinking milk lead to increased fractures?

Milk has always been associated with strong bones due to the high amount of protein and calcium in it. Yet reading it up on wikipedia, A study published in The BMJ that followed more than 45,000 ...
0
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1answer
296 views

How exactly is casein digested?

I mean it seems first step is rennin or pepsin digestion in stomach - then what happens with remaining peptides? I am interested in the whole process from casein to amino acids. Is there brush border ...
10
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1answer
102 views

Do mosquitos excrete blood?

Since insects like mosquitos ingest only blood, and insects generally excrete their solid and liquid waste at the same time as frass, I was wondering: is mosquito defecation more like iron pellets or ...
2
votes
1answer
49 views

Need an explanation of how bad garlic breath is eliminated by swalllowing a bit of raw garlic

Please bear with me, as I am just a poor physicist. I have learned how to make traditional pastourma from a recipe given by my late aunt Dora, which is like pastrami except with a very strong garlic ...
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0answers
19 views

Why fat droplets are transmitted in lacteal

I wanted to know why fat droplets are transmitted in lacteals of the stomach instead of being transmitted in the blood capillaries? Thank you in advance.
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1answer
41 views

Microbiome Context for Amino Acid Essentials and Non-Essentials

Given what we are now learning about the diverse mix and variance of microbiomes (aka bacterias via human gut project), is it possible that synthesis of aminos can be done by specific bacteria and ...
3
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0answers
161 views

Plant vs animal protein digestibility?

The protein scoring methodologies ( https://en.wikipedia.org/wiki/Protein_Digestibility_Corrected_Amino_Acid_Score) rate plant proteins of a lower quality than animal proteins. Now I can understand ...
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1answer
369 views

Does pepsin digest plant protein?

This may sound trivial, but... Protein is sourced from plants and animals. Pepsin and HCl digest meat (animal protein). Does pepsin also digest plant-based proteins? I took a look at few articles ...
0
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1answer
411 views

Would modifying the human microbiome to digest cellulose be worth it? [closed]

I've read that cellulose has a lot of calories that go unused. I was wondering how practical it would be to incorporate a bacteria capable of suggesting cellulose into the human gut. I would say that ...
0
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0answers
29 views

Feeding animals or plants with coffee?

What happens if you feed animals or plants with coffee? Say, just once, or daily? There are some extra coffees in the pot, and I don't know whether it is a good idea feeding animals or plants with ...
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0answers
29 views

Raw food diet digestion

I haven't really paid attention to the raw food diet and the claims of its supporters until now. A passage from this website says: The basic premise behind preparing raw food is not to cook food ...
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0answers
283 views

Which enzyme curdles milk in human infants? [duplicate]

Following, this question - Do humans produce rennin? Rennin does not exist. And What inactivates pepsin in infants? Rennin exist. What do I know is- Rennin is found in calves and acts on milk to ...
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1answer
380 views

Can Fluoride be absorbed into the blood from within the mouth without swallowing?

I'm having a discussion with somebody regarding Fluoride usage. I told him that even if he doesn't like the idea of ingesting it, brushing and spitting it out will do you no harm. He then said this: ...
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0answers
33 views

Does starch need to be cooked?

Does starch need to be cooked for human digestion ? Is the answer different for different starches; potato , wheat, corn, etc ?
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2answers
832 views

Is starch and glycogen digestion intra or extracellular?

Do humans have the enzyme for starch intracellular digestion? Also, do plants have the ability to digest Glycogen? Intra or extracellular, or both?
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0answers
36 views

Chewing and weight loss/gain

I have a burning question. I have read many articles which say that chewing food properly, therefore longer, till you have a liquid-like texture, is causing you to eat less calories. However, it ...
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0answers
30 views

Energy cost of chewing vs production of enzymes

Consider a hypothetical case that you ingest a piece of starch. Which is more costly energetically 1) chewing + reduced amount of enzymes production needed or 2) sole production of all the enzymes for ...
3
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2answers
246 views

Carbohydrates in acidic stomach

How does the acidic environment in the stomach affect carbohydrate and fast digestion? Does it aid, impede or remain neutral in their digestive process. Or do the carbs and fats leave the stomach (...
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0answers
61 views

Does hunger necessarily mean that we should eat?

People feel hunger sooner after they eat food that consists mostly of carbohydrates. For example, if someone eats a good portion of rice then most likely they will be hungry after a couple of hours. ...
3
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0answers
77 views

Is human blood useful as food?

Lacking other resources, could a healthy adult slit his wrist to feed a starving child with his blood? Would it be nutritional and would a starving dehydrated child eat it?
8
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1answer
1k views

Human Digestion of Cellulose?

Most animals can digest the cellulose in grass because of the anaerobic bacteria called Fibrobacter succinogenes living in their rumen (gut). The bacteria produces the enzyme cellulase and is ...
3
votes
1answer
27 views

Why is secretin sensitive to acid?

My textbook says, secretin secretion is triggered by the presence of acidic chyme in intestine. But why is secretin sensitive to acidic environment? I checked the wikipedia page of secretin and found ...
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0answers
204 views

Why do we have bacteria in our alimentary canal? [closed]

Our alimentary canal contains lots of bacteria. Most of these are found in the small intestine and large intestine. Can you a give a few reasons why is it a good thing to have bacteria in our ...
4
votes
1answer
479 views

Why is pollen used as a dietary supplement?

Sporopollenin is the hardest biological substance and can't be degraded by any know enzyme (my school textbook). Then why is pollen used as a dietary supplement if it can't be digested? Also, pollen ...
4
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2answers
246 views

Betaine HCl stomach pH

It seems betaine HCL is often recommended for those suffering from "low stomach acid" -- which, as I understand, is having too high stomach pH for proper digestion (especially for proteolysis via ...
3
votes
1answer
125 views

Can I dry digested protein sample over weekend in a vacuum concentrator?

I have digested with trypsin the tissue protein extract for mass spectrometry, and forgot to transfer the sample from the SpeedVac to the -80C freezer. As I did this on Friday, I can transfer the ...
6
votes
1answer
1k views

Digestion of milk in humans

The intial step in the digestion of milk in humans is carried out by which of the following enzymes? A) lipase. B) trypsin. C) rennin. D) pepsin. I'm confused between the C and D option. as it'...
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1answer
356 views

Is some of the energy of food lost during digestion?

I know that chemical energy of food is converted to heat energy to be used by the body in many metabolic reactions. Specifically, I know that the breaking down of bonds is what releases energy. Does ...
8
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1answer
4k views

How do bile salts affect lipase activity?

BACKGROUND: It is well known that bile salts are needed for emulsification of fats. It is then said that this increases the surface area for activity of pancreatic lipase, implying that bile salts ...
3
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1answer
511 views

Cholesterol and fatty acids role in bile? [closed]

The composition of gallbladder bile is 97% water, 0.7% bile salts, 0.2% bilirubin, 0.51% fats (cholesterol, fatty acids and lecithin)1. Bile's role is mainly help for digestion of lipids via bile ...
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1answer
89 views

How is chewing gum processed?

There is the common belief that Chewing gum takes 7 years to digest But is this actually true? Does it really stick to your intestines for 7 years, or is it processed like all foods, except it isn'...
6
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2answers
305 views

How Anopheles crop doesn't digest gametocytes of P. vivax?

Background According to my A-level textbook: When Anopheles mosquitoes inject their proboscises and suck up blood from human host of malaria agent, they suck all stages of malaria parasite present in ...
5
votes
2answers
360 views

Can you eat enough to make your stomach explode?

Background After eating a large meal last night, I noticed that my tummy had significantly enlarged. After that, I started wondering if eating too much could cause a stomach to explode. Could this ...
6
votes
1answer
2k views

Is aquafaba readily digestible?

I have always drained and tossed the water from canned beans. My understanding has been that the water that canned beans are soaked and cooked in contains raffinose, the gas-causing sugars that humans ...
3
votes
1answer
41 views

How does horse extract the energy to needs from a relatively small digestive system?

Recently I saw Inside nature's gaints episode on horse, and was fascinated about its internal organisation. And my question is that they have a very large lungs to accommodate, but a relatively ...
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1answer
117 views

Secondary/ Acquired lactose intolerance

Acquired lactose intolerance may occur due to a sudden and high intake of milk-based diets. Lactase is an inducible enzyme. So if lactase is an inducible enzyme then why increase intake of lactose is ...
5
votes
1answer
131 views

How does hydration affect digestion?

My textbook( biochemistry by Satyanarayana, 4th edition pg.no:166) says: The polysaccharides get hydrated during heating which is essential for their efficient digestion. (I think there is a typo ,...
0
votes
1answer
122 views

Digestion Enzymes in Carbohydrate Metabolism?

Digestion of carbohydrates is ending in small intestine with mainly disaccharidases. Isomaltose is broken down to 2 molecules of glucose by the enzyme called alpha dextrinase(oligo-1,6 glucosidase or ...