9 votes

Why is carbon dioxide produced in alcohol fermentation but not in lactic acid fermentation?

Glycolysis needs a steady supply of NAD+ to happen - this is the driver for the anaerobic oxidation to lactate and ethanol, although this is energetically much less favorable than the complete ...
Chris's user avatar
  • 51.6k
7 votes

Why do animals use glycogen for their polysaccharide storage whereas plants use starch?

well glycogen can be broken down into sugars a lot faster, many more branches means many more ends to clip individual sugars off of, that's how you mobilize the sugar for use, it is clipped of the end ...
John's user avatar
  • 14.7k
6 votes

Can fructose take multiple forms ? Which of these structures of fructose is correct?

The two structures on the left are correct; the one on the upper left is the alpha-D-fructofuranose form, while the one on the lower left is the beta-D-fructofuranose form. Fructose is a ketohexose (a ...
Vikki's user avatar
  • 240
5 votes
Accepted

Why do animals use glycogen for their polysaccharide storage whereas plants use starch?

Summary The key difference between glycogen and amylopectin (the main constituent of starch) is not the number of α l,6-glycosidic branches, but their arrangement. In glycogen branches are ...
David's user avatar
  • 25.7k
5 votes

Can a human being live without any carbohydrates?

The Atkins diet is based on that. Without carb intake, however, the citric acid cycle (CAC) eventually basically stops and proteins will be utilized to be converted to carb intermediates to feed the ...
AliceD's user avatar
  • 52.4k
4 votes
Accepted

Is aquafaba readily digestible?

Much of it is not readily digestible. According to this chemical analysis: Finally the results presented here also indicate that the amount of digestible carbohydrates in aquafaba is minimal. For ...
Jason C's user avatar
  • 638
4 votes

Carbohydrates in acidic stomach

As for the digestion of fats there are two digestive enzymes active in the stomach: Lingual lipase (produced with saliva) Gastric lipase (produced in the stomach chief cells) Both have activity ...
adjan's user avatar
  • 2,106
4 votes
Accepted

Why is it possible to make yoghourt with lactose-free milk?

Conversion of lactose to galactose and glucose is a part of the bacterial metabolism of lactose. So digested lactose would work. In fact, it should work for all kinds of 6-carbon sugars as lactic ...
WYSIWYG's user avatar
  • 35.6k
4 votes
Accepted

How can cane sugar sucrose be different from beet sugar in regard to carbon-13 content?

The differential uptake of different isotopes of carbon is covered well at: https://en.m.wikipedia.org/wiki/Fractionation_of_carbon_isotopes_in_oxygenic_photosynthesis Plants have a lower proportion ...
Polypipe Wrangler's user avatar
4 votes
Accepted

Why is fructolysis independent of glycolysis?

Summary The mechanistic reason why fructose is converted to fructose 1-phosphate by fructokinase rather than fructose 6-phosphate by hexokinase is explained in terms of the Km values of fructose and ...
David's user avatar
  • 25.7k
3 votes

Why is beta- D fructofuranose two different structures when in free form and as part of sucrose?

I'll try to explain this to you, but you should really look it up here: https://pubchem.ncbi.nlm.nih.gov/compound/beta-Levulose#section=3D-Conformer&fullscreen=true This is the structure of beta-...
Rishika Sharma's user avatar
3 votes

What allows grass eaters to digest cellulose?

No there is something else missing besides bacteria humans often already have the right bacteria but they don't digest most of the cellulose they ingest because digesting cellulose with bacteria is ...
John's user avatar
  • 14.7k
3 votes
Accepted

What is the carbohydrate found in almonds, cashews, pecans, hazlenuts and pistachios?

Firstly you must realize that all the above mentioned nuts are actually the seeds of plants. So the question now is which carbohydrate is mainly found in seeds of plants. During the double ...
user35897's user avatar
  • 1,260
3 votes

Sugars which are Carbohydrates and vice-versa?

You need to make a distinction between polymers and monomers (or dimers). Typically, sugars are monomers like glucose, maltose, or fructose. Sucrose (table sugar) is a dimer. These are all ...
mdperry's user avatar
  • 3,517
3 votes
Accepted

Living on pure glycogen?

You asked three questions here, so I'll answer them one by one. Yes, you can survive with glycogen as the only source of carbohydrates, assuming that you also take other nutrients like proteins, fats,...
another 'Homo sapien''s user avatar
3 votes

What is the relationship between the light and dark reactions of photosynthesis?

Apology This question has a very simple answer which was provided in a comment by @EliKorvigo (and acknowledged by the poster) two years before writing this answer. However the commenter did not post ...
David's user avatar
  • 25.7k
3 votes
Accepted

Human Body's rate of conversion of carbs, protein and fat into energy?

It is quite complicated, the speed of conversion of carbohydrates, protein and fat in to energy is definitely not linear and dependent on what the body is doing. You should be close to right in ...
Vilut's user avatar
  • 101
3 votes
Accepted

If protein is mostly used by the body for purposes other than extraction of energy, why are calories from protein relevant?

Preamble I had not intended to answer this question as I felt it lacked the clarity required for this site. However I now think that it is necessary to correct the assertion that “protein has to be ...
David's user avatar
  • 25.7k
2 votes

Solubility of Amylopectin and Glycogen in water

The question is incorrect in asserting that the only difference between amylopectin and glycogen is their extent of branching. This is only an incidental difference. As I explain in more detail in ...
David's user avatar
  • 25.7k
2 votes

Carbohydrate in egg white

The one I found is Ovomucin,though it's not a pure carbohydrate. Ovomucin is a highly glycosylated protein and approximately 33% of ovomucin is made up of carbohydrates. Nutritional Values of Egg ...
Tyto alba's user avatar
  • 8,782
2 votes

Sugars which are Carbohydrates and vice-versa?

Although one might naïvely imagine that the term carbohydrate is used for a molecule containing carbon, hydrogen and oxygen, this is not the case as, if so, it would include compounds like fatty acids....
David's user avatar
  • 25.7k
2 votes

How is the rate of gluconeogenesis controlled in the cell?

In mammals gluconeogenesis occurs primarily in the liver (together with the kidney to a much smaller extent). When the blood glucose concentration falls, it is the role of the liver to generate ...
David's user avatar
  • 25.7k
2 votes

Carbohydrates in acidic stomach

People who have no stomach acid because of medicine or surgery still digest their foods. Otherwise you would predict incomplete digestion / weight loss / diarrhea would be a consequent of stomach ...
Willk's user avatar
  • 2,964
2 votes

Sugars which are Carbohydrates and vice-versa?

The statement in your question is correct. All sugars are carbohydrates but not all carbohydrates are sugars. In fact, sugars are by definition carbohydrates. Wikipedia defines sugars as : Sugar ...
March Ho's user avatar
  • 9,452
2 votes
Accepted

If humans had cellulase would they be able to digest grass?

No. Even for an herbivore, digesting grass, or plants to be more general, is hard, because they contain cellulose. Herbivores have different parts of a stomach, whereas humans only have one ...
Josh Vicente's user avatar
2 votes
Accepted

What is the source of the fat in adipose tissue?

The proximal source of adipocyte lipids is mainly fatty acids from circulating lipoproteins (1) after hydrolysis by lipoprotein lipase (LPL). LPL is activated by ApoC-II, which is present in hepatic-...
Eliane B.'s user avatar
  • 1,145
2 votes

Meaning of a negative value for non-fiber, non-sugar carbohydrate based on a nutrition label

The values on the nutrition label from the question (11 g total carbs, 9 g sugars, 3 g fiber) could be actually explained by rounding: Total carbohydrates: 11.45 (rounded to 11) Sugars: 8.55 g (...
Jan's user avatar
  • 8,079
2 votes

Meaning of a negative value for non-fiber, non-sugar carbohydrate based on a nutrition label

The individual values in the OP's onion label are not out of line with the U.S. Department of Agriculture's reference data. There are two of the latter, one for "Onions, raw" and one for "Onions, ...
mgkrebbs's user avatar
  • 9,054
2 votes
Accepted

How can we digest lactose even though it has Beta glycosidic linkages?

One simple reason is physical interaction. lactose is only composed of two sugars, while cellulose is giant network of interlocked sugars. Cellulose keeps the sugars tightly packed in three ...
John's user avatar
  • 14.7k
2 votes

Proteoglycans vs Glycoproteins

More context would be helpful, but it's possible the data from the Quora post was incorrectly transcribed from a table on this biotech site, which states that the carbohydrate content of proteoglycans ...
acvill's user avatar
  • 8,296

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