Endocrine system and metabolic reactions Flashcards
WHAT IS GLYCOGENESIS
synthesis of glycogen from glucose
WHAT EFFECT DOES GLYCOGENESIS HAVE ON BGL?
Decreased BGL
WHAT HORMONE STIMULATES GLYCOGENESIS?
Insulin
WHAT IS GLYCOGENOLYSIS?
breakdown of glycogen to form glucose
WHAT EFFECT DOES GLYCOGENOLYSIS HAVE ON BGL?
increased BGL
WHAT HORMONES STIMULATE GLYCOGENOLYSIS?
glucagon and adrenaline
WHAT IS GLUCONEOGENESIS?
synthesis of glucose from glycerol, amino acids and lactic acid
WHAT IS THE EFFECT OF GLUCONEOGENESIS ON BGL
increases BGL
WHAT HORMONES STIMULATE GLUCONEOGENESIS
cortisol and glucagon
WHAT IS LIPOLYSIS?
breakdown of triglycerides into glycerol and fatty acids
WHAT IS THE EFFECT OF LIPOLYSIS ON BGL?
increase BGL
WHAT HORMONES STIMULATE LIPOLYSIS?
adrenaline, cortisol, thyroid hormones, growth hormone
WHAT HORMONE STIMULATES LIPOGENESIS?
insulin
WHAT EFFECT DOES LIPOGENESIS HAVE ON BGL?
decreased BGL
WHAT IS LIPOGENESIS
synthesis of lipids from glucose and amino acids
What is the definition of catabolism?
break down molecules and are intended to produce energy
What is the definition of anabolism?
is the chemical reaction that joins simple molecules together to form complex molecules.
Describe what happens during glycogenesis, the effect it has on BGL, and what hormone stimulates this reaction
- Glycogenesis is the formation of glycogen from glucose and occurs in liver and muscle cells
- If there’s more glucose than needed the molecules of glucose are joined together to form glycogen
- Glycogenesis decreases blood glucose levels when they’re high allowing glycogen to be stored in liver and muscle cells.
- Glycogenesis is stimulated by the hormone insulin.
Describe what happens during glycogenolysis, the effect it has on BGL, and what hormone stimulates this reaction
- Glycogenolysis occurs when blood glucose level is low, causing glycogen stored in the liver to break up to release glucose into the bloodstream
- Causes BGL to increase
- Glycogen stored in skeletal muscle cells is broken down to glucose, to make ATP for that muscle
- main hormones responsible for glycogenolysis are glucagon and adrenaline
Describe what happens during gluconeogenesis, the effect it has on BGL, and what hormone stimulates this reaction
- Gluconeogenesis is the process by which the body produces glucose from lipids and proteins when the BGL drops and glycogen stores are used up the liver.
- Increases BGL
- Gluconeogenesis is stimulated by the diabetogenic hormones (glucagon, growth hormone, epinephrine, and cortisol).
Describe what happens during lipogenesis, the effect it has on BGL, and what hormone stimulates this reaction
- Occurs when the intake of carbohydrates, proteins or fats exceeds the body’s ATP/energy needs.
- results in creation of triglycerides, which are stored in the adipose tissues.
- main hormone responsible is insulin
- decreases BGL
Describe what happens during lipolysis, the effect it has on BGL, and what hormone stimulates this reaction
- Lipolysis is the breakdown (catabolism) of triglycerides into glycerol & fatty acids
- increases BGL
- main hormones involved are adrenaline, cortisol and thyroxine
Where is glycogen stored?
liver and muscles
Name the two products resulting from lipolysis & what they are used for
- Glycerol is converted into pyruvate (pyruvic acid) & enters the Krebs cycle to produce ATP
- Glycerol can also be converted to glucose by gluconeogenesis
- Fatty acids are converted into acetyl coenzyme A (CoA) in the liver, which then enter the Kreb’s cycle to form ATP
- But if the levels of CoA produced are too high for the Krebs cycle to process the liver converts the CoA into ketone bodies