Metabolic Pathways Overview

<p>Conversion of dihydroxyacetone phosphate to glyceraldehyde 3-phosphate (C)</p> Signup and view all the answers

<p>Glycogen storage disease type 12 (B)</p> Signup and view all the answers

<p>There is rapid synthesis and degradation of proteins. (A)</p> Signup and view all the answers

<p>Amylase (A)</p> Signup and view all the answers

<p>They accumulate and are excreted. (B)</p> Signup and view all the answers

<p>It is necessary for enzyme activation. (B)</p> Signup and view all the answers

<p>They do not participate in metabolic adjustments. (C)</p> Signup and view all the answers

<p>It illuminated hereditary conditions linked to enzyme defects. (C)</p> Signup and view all the answers

<p>Polysaccharides and disaccharides. (B)</p> Signup and view all the answers

<p>6-7 (B)</p> Signup and view all the answers

<p>It is a key intermediate in several pathways. (D)</p> Signup and view all the answers

<p>Glucokinase (D)</p> Signup and view all the answers

<p>It functions only at elevated glucose concentrations. (C)</p> Signup and view all the answers

<p>Indirect inhibition by fructose 6-phosphate. (C)</p> Signup and view all the answers

<p>Nonspherocytic Hemolytic Anemia (B)</p> Signup and view all the answers

<p>It reduces further metabolism and inhibits hexokinase. (C)</p> Signup and view all the answers

<p>It phosphorylates glucose and other hexoses. (B)</p> Signup and view all the answers

<p>Direct inhibition by glucose 6-phosphate. (C)</p> Signup and view all the answers

<p>NADH is oxidized to NAD+ through lactate conversion. (D)</p> Signup and view all the answers

<p>Less energy is produced per glucose molecule. (A)</p> Signup and view all the answers

<p>Glucokinase (C)</p> Signup and view all the answers

<p>It produces energy in the form of ATP without mitochondria. (D)</p> Signup and view all the answers

<p>Phosphorylation of intermediates at the expense of ATP. (C)</p> Signup and view all the answers

<p>Kidney tubules and intestinal mucosa. (A)</p> Signup and view all the answers

<p>Two molecules of ATP. (C)</p> Signup and view all the answers

<p>It donates a phosphate group in the presence of Mg. (A)</p> Signup and view all the answers

<p>Autosomal recessive (A)</p> Signup and view all the answers

<p>It aids in the storage of glucose as glycogen. (C)</p> Signup and view all the answers

<p>Permanent neonatal diabetes mellitus (B)</p> Signup and view all the answers

<p>Mild hyperglycemia (B)</p> Signup and view all the answers

<p>30%–60% (D)</p> Signup and view all the answers

<p>Phospho glucose isomerase (B)</p> Signup and view all the answers

<p>Pancreatic β-cells (B)</p> Signup and view all the answers

<p>It occurs at higher serum glucose levels. (C)</p> Signup and view all the answers

<p>To phosphorylate fructose 6-phosphate to fructose 1,6-bisphosphate (A)</p> Signup and view all the answers

<p>Accumulation of abnormal glycogen in muscle tissue (A)</p> Signup and view all the answers

<p>Fructose 2,6-bisphosphate (B)</p> Signup and view all the answers

<p>Diastase-resistant and filamentous (A)</p> Signup and view all the answers

<p>It is an enzyme responsible for the formation of fructose 2,6-bisphosphate. (A)</p> Signup and view all the answers

<p>It produces fructose 1,6-bisphosphate and is rate-limiting. (B)</p> Signup and view all the answers

<p>Renal failure (A)</p> Signup and view all the answers

<p>It maintains glycogen synthase in its active form. (D)</p> Signup and view all the answers

Breakdown of glucose to pyruvate without oxygen. Produces less ATP than aerobic glycolysis but faster.

First five reactions of glycolysis where ATP is used to phosphorylate glucose and its derivatives.

The continuous process where proteins are synthesized and degraded within a cell, maintaining a dynamic balance.

Last three reactions of glycolysis where ATP is produced by substrate-level phosphorylation.

A state where the synthesis and degradation rates of proteins are equal, even though there's constant turnover.

Direct transfer of a phosphate group from a substrate molecule to ADP, generating ATP.

Enzymes that initiate and regulate protein synthesis, influencing the overall rate of protein turnover.

Hereditary conditions where a specific enzyme is defective, leading to accumulation and excretion of the substrate.

Enzyme that phosphorylates glucose to glucose-6-phosphate specifically in liver cells.

Enzyme that phosphorylates glucose to glucose-6-phosphate in liver and other tissues.

Carbohydrates consumed through food, consisting of polysaccharides like starch and glycogen, disaccharides like sucrose, lactose, maltose, and small amounts of monosaccharides like fructose and pentoses.

An enzyme found in saliva that breaks down carbohydrates (specifically starch) into simpler sugars.

Movement of glucose into cells.

The type of salivary amylase responsible for breaking down carbohydrates, requiring chloride ions (Cl-) for activation and working best at a pH of 6-7.

Insulin facilitates glucose uptake in skeletal muscle, cardiac muscle, diaphragm, and adipose tissue.

The process of chewing food, breaking it down into smaller pieces to aid in digestion.

It's the central molecule in several metabolic pathways like glycolysis, glycogen synthesis, glycogen breakdown, gluconeogenesis, and the pentose phosphate pathway.

A step in a metabolic pathway that commits a molecule to a particular pathway, making it difficult to reverse the process.

Hexokinase is inhibited by its product, glucose-6-phosphate, when further metabolism is reduced.

Glucokinase requires a higher glucose concentration for optimal activity, meaning it is only active when blood sugar is high.

Glucokinase activity is inhibited by its product, glucose-6-phosphate.

A rare genetic disorder where hexokinase activity is significantly reduced, leading to a specific type of anemia.

The enzyme PFK has different subunits (M, L, P) encoded by different genes. Mature muscle expresses only the M subunit, while erythrocytes express both M and L subunits.

Although PFK deficiency affects erythrocytes, they can still function because the L subunit allows for a functional enzyme to be produced.

Aldolase A cleaves fructose 1,6-bisphosphate into dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, a reversible reaction that is not regulated.

An autosomal recessive mutation in the ALDOA gene can cause Aldolase A deficiency, which can lead to hemolytic anemia, rhabdomyolysis, and glycogen storage disease type 12 (GSD12).

This enzyme interconverts dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, ensuring that both molecules can be further metabolized in glycolysis.

A symmetrical molecule formed by phosphorylation of fructose-6-phosphate at the 1-position by phosphofructokinase-1 (PFK-1).

The enzyme responsible for catalyzing the irreversible and rate-limiting step in glycolysis: converting fructose-6-phosphate to fructose 1,6-bisphosphate.

PFK-1 is regulated by the availability of its substrates, ATP and fructose-6-phosphate.

A regulatory molecule that activates PFK-1, boosting glycolysis.

A genetic disorder characterized by a deficiency in the muscle-specific subunit of PFK-1, affecting muscle and red blood cell metabolism.

An abnormal form of glycogen that accumulates in PFK deficiency due to increased glucose-6-phosphate (G6P) levels.

An enzyme that promotes glycogen synthesis. Activated by G6P.

Complications that may occur in PFK deficiency due to prolonged ischemic exercise.

GCK-MODY, also known as MODY2, is a type of diabetes caused by mutations in the GCK gene. It is characterized by mild hyperglycemia and is often diagnosed in childhood.

GCK-MODY is caused by mutations in the GCK gene, which encodes the enzyme glucokinase. This enzyme is crucial for glucose sensing in the pancreas and liver.

In the pancreas, glucokinase acts as a glucose sensor, triggering the release of insulin when blood sugar levels rise. Mutations in GCK-MODY lead to a higher glucose threshold for insulin release.

In the liver, glucokinase helps store glucose as glycogen after meals. Mutations in GCK-MODY impair this process, contributing to mild hyperglycemia.

GCK-MODY is inherited in an autosomal recessive manner. This means a person needs to inherit two copies of the mutated gene, one from each parent, to develop the condition.

The conversion of glucose 6-phosphate to fructose 6-phosphate is catalyzed by phosphoglucose isomerase. This reaction is reversible and not a rate-limiting step in glycolysis.

NSHA can arise due to genetic changes in the HK1 gene, which is inherited in an autosomal recessive manner.

Individuals with NSHA may also experience multiple malformations, panmyelopathy, and latent diabetes.