Blood Glucose Regulation

Questão	Responda
Normal glucose level	5mmol/L
Where is glucose stored?	Liver and skeletal muscles
Processed foods contain ___ which is more easily digested than natural ____	sucrose , starch sucrose is absorbed very quickly and can lead to diabetes
Glucose can be derived from what	breakdown of surplus amino acids in the liver
How does glucose from digestion arrive at the liver?	Hepatic portal vein
what is glucose	monosaccharide C6H12O6
How does glucose release energy	Glucose > pyruvic acid > ATP release energy for movement, chemical synthesis, and nerve activity.
What organ is glucose particularly important for?	important to the brain – uses no other fuel (except in starvation mode)
What does the liver do with surplus glucose?	Stores as glycogen (complex storage molecule) After a meal the liver can store up to 10% of its mass as glycogen (sustain for 2 days)
Where can glucose also be stored	Glycogen is also stored in muscles
What happens between meals	glycogen is broken into glucose and released back into the bloodstream
Function of insulin	Increase glycogen and fat synthesis and glycogen breakdown inhibited DECREASE BLOOD GLUCOSE LEVELS
Function of glucagon	Decreased glycogen and fat synthesis and glycogen breakdown stimulated INCREASE BLOOD GLUCOSE LEVELS
Where are the hormones secreted?	Secreted in the pancreas (sensor) known as the Islets of Langerhans (part of endocrine system)
Alpha cells	secret glucagon in response to low blood glucose to increase blood glucose concentration
Beta cells	secret insulin in response to high blood glucose to decrease concentration
What does insulin stimulate?	uptake of glucose by cells for cellular respiration, or liver cells to convert glucose to glycogen for storage. When glycogen store is full surplus is converted to fat.
What does the inability of beta cells to be produced lead to?	diabetes
How do the Islets work?	independent of nerve control, they monitor and detect changes in blood glucose concentration and release appropriate hormone in correct amounts (both sensors and controllers)
What does the body resort to when glycogen stores are used?	• FAT is converted to fatty acids and glycerol (used respiration) • Glucose can be produced from protein (dangerous) • The hypothalamus controls appetite =stimulate
Target of effector insulin	liver, skeletal muscles, fat cells = convert glucose to glycogen and store in in insulin
Target of effector glucagon	liver only = liver cells receive glucagon and convert glycogen into glucose then release it
How does glucose enter the brain?	facilitated diffusion
How does glucose enter muscle and fat cells?	Insulin receptors control if glucose transporters are present or not in cell membrane
What specific glucose transporter provides a channel when insulin is present?	GLUT4 (usually inside cell, only present on surface when insulin present – to inhibit transport)
Name of process excreting GLUT4	exocytosis
What happens after insulin binds to insulin receptor	Enzyme activity is activated in insulin receptor. Signal is then transmitted from extracellular environment to intracellular without the hormone entering the cell.
What happens after chain reaction of enzymes is activated?	vesicles containing GLUT4 move to plasma membrane which fuse with plasma membrane so GLUT4 is outside plasma membrane where it can transport glucose into muscle or fat cells.
How does the body prevent excess glucose being release?	the body breaks down insulin quickly – more will only be sent to cells if more glucose is needed
Which two hormones are presented in glucose emergencies?	Adrenaline and Cortisol
Adrenaline	Secreted by adrenal medulla in adrenal gland in times of fear and danger to increases heart rate and blood pressure Causes rapid breakdown of glycogen in the liver and release of glucose into the blood
Cortisol	Secreted by adrenal cortex in adrenal gland in times of stress and starvation Simulates production of glucose from non-carbohydrate sources (amino acid / protein)
Type One diabetes is caused by what?	auto immune destruction of beta cells (no insulin produced). Can appear at any age
How is glucose monitored in Type 1	food intake, insulin injections several times a day
Why is injected insulin less effective than natural?	injected it takes longer to act than naturally secreted insulin from pancreas. The body usually monitors how much to inject (beta cells) but a type 1 person has to guess.
hyperglycemia	excess glucose
hypoglycemia.	Too little glucose may become confused or unconscious
What is type 2 caused by?	life style (obesity) and genetic influence
How does type 2 develop?	Insulin produced in pancreas but cells become resistant and insulin inhibits entry of glucose to cells
Diagnosis and Causes of type 2	Symptoms develop slowly (tiredness and weight loss). Insulin defense means higher glucose levels. Diagnosis based on blood test.
Prevention of type 2	Active lifestyle with regular exercise Eat less food (obesity is major factor) Eat less high sugar food Chose food with low glycemic index (GI) as they are digested and absorbed more slowly to reduce sugar rush effect.
5 long term consequence of type 2	1. Kidneys 2. Ketosis 3. Eye sight 4. Circulation 5. Heart
Type 2 Kidney effect	Above 11mmolL-1 glucose appears in urine. Osmotic imbalance develops, water moves out of the blood causing excessive volume of urine. This creates excessive thirst. Also cause permanent damage to glomeruli – causes kidney damage and people need dialysis.
Type 2 ketosis effect	Diabetes results in by-product known as ketone bodies. These tend to reduce blood pH. Ketones can cause breath of badly controlled diabetics to smell like nail polish remover.
Type 2 eyesight effect	can cause peripheral vascular disease (PVD) = damage to small blood vessels. This can result in retina damage and then blindness
Type 2 circulation effect	PVD can also cause problems to blood supply to feet and hands. Persistent infections and gangrene set in, and high proportion of advanced diabetics need amputations
Type 2 heart effect	Diabetes is linked to increased changes of coronary artery disease

Próximo

Blood Glucose Regulation

Descrição

Resumo de Recurso

Semelhante

	Criado por ameliavincent123 mais de 9 anos atrás