blood glucose homeostais

what is ythechemical formula for glucose?

C6H12O6

name a simple sugar

a monosaccaride

why do cells need a constant supply of glucose?

for a source of energy for all activities such as movement, reproduction, synthesising molecules, active transport

what is the formula for cellular respiration?

C5H12O6 + O2—> CO2+ H20+ Energy

glucose is a…

digestive carbohydrate

where does the glucose come from in our body?

it is in the food that we eat. Carbohydrates in our food are broke down into glucose during digestion and then absorbed into the blood through the walls of the intestine.

any excess glucose in the blood must be removed and stored ready for use cellular a activities between meals. how is this stored?

as glycogen in the liver and muscles

what is glycogen

is a long chain of glucose

what is the normal range for glucose?

90mg/100ml this rises sharply after a meal .

how much glycogen can the body store?

about 500g. about 100g is stored in the liver and remainder is in the skeletal muscle cells

what is the role of the liver in blood glucose homeostasis.

is an effector (along with body cells) it is able to convert glucose into glycogen for storage or glycogen to glucose for release into blood

what is glycogenesis

the formation of glycogen from other carbohydrates

what is glycogenolysis

breakdown of glycogen to glucose

what is Glucoegenesis?

is the conversion of fats to proteins into glucose

the liver blood supply comes from where?

the hepatic portal vein

what does the hepatic portal vein do?

it brings blood directly from the stomach, spleen, pancreas, small and large intestines. therfore the liver has the first change to absorb nutrients from digested food

what happens after a meal?

there is an increased proportion of carbohydrates consumed therefore the breakdown of products (mainly glucose) is absorbed into the blood capillaries of villi of the small intestine.

what is lipogenesis?

is when glucose is converted into fat for long term storage. this occurs in liver and muscle cells

what does the liver do in response to increased glucose levels?

glucose is removed from the blood to the liver from ther hepatic portal vein. the glucose produces energy for liver functioning. it can be removed by the liver and or muscle cells and then converted into glycogen for storage (glycogenesis) to it can continue to circulate in the blood, available for body cells to absorb as a source of energy. it c an be converted into fat for long term storage (lipogenesis)

glycogensis is stimulated by what?

the hormone insulin

what is glycogenolysis stimiulated by?

glucagon

where can glycogen be stored?

in liver and muscle cells

how long can the glycogen stored in the liver and muscles by used for supply?

for approx 6 hours and then the body will; use the energy stored in fats as energy

within the pancreas are clusters of hormone secreting cells called what?

islets of langerhans

what do the alpha cells secrete

glucagon

what do the beta cells secrete

insulin

beta and alpha cells are what..

receptors for glucose levels

what does insulin do
(from the beta cells)

it causes a decrease in blood glucose levels by accelerating the transport of glucose from the blood into body cells, especially skeletal muscles. accelerating conversion of glucose into glycogen in the liver and skeletal muscles (glycogenesis) stimulating the conversion of glucose into protein. and it stimulates the conversion of glucose into fats (lipids) in adipose tissue, or fat storage (lipogenesis)

what is it called when glucose is converted into proteins?

protein synthesis.

what kind of receptors are on the islets of langerhans

chemoreceptors

what does glucagon do (from the alpha cells)

it stimulates glycogenolysis, this is the conversion of glycogen into glucose (in the liver). Stimulating gluconeogenesis, the production of new sugar molecules from fats( lipids) and amino acids in the liver. This involves the liver and is called lipolysis. also having a mild stimulating effect on protein breakdown

what is lipolysis?

is the production of new sugar molecules from fats (lipids) and amino acids in the liver

what is the role of the adrenal glands in blood sugar regulation.

the secretion of gluciocortcoids by the adrenal cortex and the secretion of adrenaline and noradrenaline by the adrenal medulla

what hormone released by the hypothalamus to trigger the anterior pituitary to release Adrenocroticotripic hormone

cortiocortiopin releasing factor

the hormone cortisol is a.,..

glucocorticoid

the hormone Adrenalcorticotropic hormone stimulates what t

the adrenal cortex for the release of cortisol

what does cortisol do?

it regulated carbohydrate metabolism by ensuring that enough energy is produced to cells. in doing so they… stimulate the conversion of glycogen to glucose during glycogenolysis. They also increase the rate at which amino acids are removed from cells, mainly muscle cells, and transported to the liver. Some of the amino acids may be converted to glucose via glucogenesis if glycogen and fat levels are too low. Promote the mobilisation of fatty acids from adipose tissue (fatty tissue), allowing muscle cells to shift from using glucose to fatty acids for much of their metabolic energy

adrenaline and noradrenaline have similar effects to..

they sympathetic nerves if the autonomic nervous system

what does adrenaline and noradrenaline do in regards to increased of blood glucose

adrenaline elevates the blood glucose levels through glycogenolysis and in doing so counteracts effects of insulin. It stimulates the production of lactic acid from glycogen in muscle cells, which can then be used by the liver to manufacture glucose.