Temperature Regulation Flashcards
nutrient pools
when you eat food, the subunits of nutrients go into either pool of free AAs or free carbs and fats
conversion between pools happens in liver
amino acid pools
amino acids can be immediately used as building blocks or sometimes amino acids can be deaminated and converted into carb-lipid type substances
if deaminated, amine will be excreted as urea
carb and lipid pools
carbs and lipids can be used immediately for energy or immediately as building blocks or can go to storage
can do opposite of deamination reaction to become proteins
metabolic states
absorptive or postabsorptive
absorptive state
during/immediately after a meal
nutrient levels in bloodstream are high
major reactions at this time are anabolic
post absorptive state
not immediately after meal (much later)
GI tract is empty- not bringing nutrients into bloodstream
break down reserve/storage molecules
mostly catabolic reactions
how are glucose levels in blood homeostatically maintained?
through hormonal and neural control
hormonal control of glucose levels
pancreas produces insulin to decrease bgl and glucagon to increase bgl
insulin
major hormone of absorptive state
high bgl stimulates pancreas to produce insulin
decreases bgl
insulin actions
promote protein synthesis
stimulate glycolysis
prompt cells to take up and break down (oxidize) glucose
glucagon
low bgl stimulates pancreas to produce glucagon
causes increase in bgl
glucagon actions
stimulates glycogenolysis, gluconeogenesis, and lipolysis
when does neural control of blood glucose occur?
in post absorptive state; low bgl is stimulus
results in increased bgl
neural control of blood glucose
sympathetic stimulation changes use of glucose
most signals go to adipose tissue; causes glycolysis and gluconeogenesis
some signals go to adrenal medulla to secrete epinephrine
epinephrine acts on liver, skeletal muscle, and adipose tissue to promote glycolysis and glycogenolysis
all to increase bgl
role of epinephrine in blood glucose
neural stimulation of adrenal medulla causes secretion of epinephrine
acts on liver, skeletal muscle, and adipose tissue to promote glycolysis and glycogenolysis
functions of liver
primary: recycle red blood cells
also: makes cholesterol available to rest of body (produces VLDL and breaks down HDL)
cholesterol
structural molecule that is a part of plasma membrane
cannot travel in blood without carrier molecule- lipoprotein
lipoprotein
carrier molecule that can carry proteins or lipids