Glucose is a monosaccheride which is build up by plants during photosynthesis.

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Why is glucose our primary source of energy?

Is there any evolutionary reason for glucose being the "main" molecule used as a source of energy, beginning with glycolysis and subsequently cellular respiration (after being converted to two ...
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1answer
606 views

Why does gluconeogenesis need to exist - it seems pointless?

The gluconeogenesis pathway seems quite pointless to me. I don't understand why an organism would want to spend energy to create a molecule that can then be metabolized again for less energy? The ...
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961 views

Can Escherichia coli survive on glucose and water alone?

I am novice to biochemistry and biology in general. I am reading Lehninger Principles of Biochemistry, and I found the following sentence at the beginning of the chapter on glycolysis: A bacterium ...
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4answers
110 views

Is Insulin-Glucose dynamic Lotka-Volterra?

From Wikipedia: The Lotka–Volterra equations, also known as the predator–prey equations, are a pair of first-order, non-linear, differential equations frequently used to describe the dynamics of ...
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1answer
149 views

What constitutes the determination of a normal blood glucose level?

Several on-line resources (e.g. MedlinePlus) suggest: Normal range for non-diabetic people who are fasting should range between: 70 and 100 milligrams per deciliter (mg/dL) Non-diabetic people who ...
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4answers
344 views

Why is too much glucose harmful?

I learned the citric acid cycle in biotechnology school and how cells work; about ADP and ATP and how the Cellular respiration (C6H12O6 + 6O2 -> 6CO2+6H2O) works. I am interested in understanding why ...
3
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392 views

When glucose production is low, the brain begins using ketoacids as energy… how does that work?

Can someone very generally describe how the brain consumes ketoacids/ketone bodies when blood glucose has been completely depleted?
3
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2answers
3k views

Difference between facilitated diffusion and secondary active transport in cells

Specifically, what is the difference between facilitated diffusion carrier processes (passive transport) and secondary active transport co-transport processes (active transport)? They seem to be the ...
3
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2answers
127 views

Tracking of oxygen molecules in glucose oxidation

For this reaction, found in typical biochemistry textbook: $C_6H_{12}O_6 + 6O_2 \to 6CO_2 + 6H_2O$ I am interested in where do the oxygen atoms of $6O_2$ go. I think they go to $6H_2O$, but this is ...
3
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398 views

Why would lactate be high in diabetics?

Why are lactate level high in diabetes? For example, type II diabetes are resistant to insulin. If those patients are insulin resistant their gluconeogenesis should be working at a high rate and, ...
3
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1answer
1k views

How are non-glucose sugars metabolized in the body?

In my biology book's section on disaccharide metabolism and glycolysis, it states that sugars other than glucose must be acted upon to enter glycolysis. Let's take sucrose as an example. Sucrose is ...
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266 views

A question on glycolysis

In the first step of glycolysis, the glucose ring is phosphorylated. Phosphorylation is the process of adding a phosphate group to a molecule derived from ATP. As a result, at this point in ...
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Conversion and storage of glucose to glycogen

Why is excess glucose, synthesized to glycogen, stored only in limited amounts, as compared with lipids/triglycerides that are stored in our body? Why is mature glycogen arranged (polymerized) in 12 ...
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1answer
502 views

How is transport of glucose into prokaryotic cells different from transport into eukaryotic cells?

I was reading page 92 of Fundamentals of Microbiology, 4th edition, which states In facilitated diffusion, the substance (glucose, for example) to be transported combines with a plasma membrane ...
2
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1answer
105 views

Why is oxaloacetate made in the mitochondria?

I'm looking at the gluconeogenic pathway: Pyruvate is shuttled into the mitochondria from the cytosol, converted to oxaloacetate by pyruvate carboxylase, converted to malate which is then shuttled ...
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2answers
279 views

What are the differences between how glucagon and cortisol work to increase blood sugar?

As I understand, both cortisol and glucagon cause an increase in blood sugar concentrations. However I don't understand how they work differently or why they work separately. I would be very grateful ...
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1answer
113 views

Can you measure plasma glucose with a regular glucose meter?

I'm wondering if plasma glucose can be measured with a regular glucose meter and strips like this. I know these meters are normally used to measure whole blood glucose, but can they measure plasma ...
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0answers
30 views

In glycolysis, what is the source of the electron that makes NAD+ into NADH instead of NADH+? [closed]

I looked at the formula for the glycolysis reaction. The overall reaction seems balanced, however, I don't see anything on the left hand side of the equation that would provides the electron to ...
0
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1answer
92 views

What is the role of Aspartate Transaminase in gluconeogenesis?

I know that oxaloacetate cannot cross the mitochondrial membrane, but can instead be converted to aspartate, shuttled out, and then re-converted back to oxaloacetate. What does this have to do with ...
0
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1answer
105 views

How non-invasive blood glucose concentration measurement work?

Diabetes patients need to conduct the “fingerstick” a few times a day. One of the mechanisms of "fingerstick" is to take small amount of blood sample and put it onto a test strip. The enzyme on the ...
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Electrically facilitated active transport across a membrane

I'm trying to go back to school to do a PhD in control theory, specifically concerned with control of glucose. The glucose system can be controlled using two chemicals: insulin and glucagon. I was ...