Biochemistry 2: Metabolic Pathways Overview

A molecule that binds to an enzyme at a site other than the active site, altering the enzyme's activity.

The process of breaking down glucose to produce energy, primarily ATP.

A key regulatory enzyme in glycolysis. It is allosterically activated by fructose-2,6-bisphosphate (F2,6BP), leading to increased glycolysis.

A state where the body is breaking down stored energy sources such as fat, protein, and glycogen for fuel.

Metabolic state during fasting, burns, or during weight loss where insulin levels are low, glucagon levels are high, and substrate availability is reduced.

The liver regulates the distribution of nutrients absorbed from the digestive system through the portal vein.

The liver helps to ensure a steady supply of nutrients, even when the amount absorbed from meals varies.

Blood from the digestive system (rich in nutrients) is collected and transported to the liver by the portal vein.

The liver receives blood from the portal vein, which carries absorbed nutrients from the intestines.

The liver plays a key role in regulating nutrient levels in the body.

The process of removing an amino group from an amino acid.

The carbon skeleton of an amino acid after deamination.

A three-carbon molecule produced from the breakdown of glucose in glycolysis.

A two-carbon molecule that is a key intermediate in energy metabolism.

The process of breaking down molecules to release energy.

The process of breaking down amino acids for energy or other uses.

Metabolic processes shift in the body depending on whether you're eating or fasting. These changes are opposite of each other, with mechanisms like enzyme activation working to achieve either energy storage or release.

Enzymes in the body can be activated by the addition of a phosphate group. This process, called phosphorylation, is involved in regulating the flow of substrates in both fasting and well-fed states.

Amino acids that are not used for protein synthesis in the liver are released into the bloodstream.

When you're fasting, your body needs to use energy reserves, leading to the breakdown of stored carbohydrates and fats (catabolism). These processes provide the necessary fuel for your cells.

The brain is a special organ that primarily relies on glucose for energy. It doesn't store much fat or glycogen, so it needs a constant supply of glucose.

Amino acids are used for protein synthesis in various tissues throughout the body.

The body uses amino acid degradation to replace amino acids that are broken down during the post absorptive state.

Metabolic processes are tightly regulated to ensure that the body has enough energy regardless of whether you're eating or fasting.

The process of synthesizing glucose from non-carbohydrate sources, primarily in the liver, to maintain blood glucose levels during fasting or prolonged starvation.

Ketone bodies are alternative fuels for the brain during prolonged fasting, produced by the liver from fatty acids.

The process of breaking down muscle proteins into amino acids to be used for gluconeogenesis during prolonged fasting.

The need for gluconeogenesis decreases during prolonged fasting as the brain begins to utilize ketone bodies as its primary energy source.

The need to break down muscle proteins for gluconeogenesis decreases as the brain begins to utilize ketone bodies as its primary energy source.