Final (ch 19) Flashcards
This compound does not overlap between several pathways
cholesterol
The a cells of pancreatec islets secrete this in response to these glucose levels
glucagon
low
When cyclic AMP is a second messenger this happens to the target enzyme
it is phosphorylated with cyclic AMP as the source of the phosphate group
glycogen phopshorylase has its greatest activity when in this state, glycogen synthase has its greatest activity when in this state
phosphorylated
not phosphorylated
the effect of epinephrine upon the liver is most similar to which hormone
glucagon
What are the hormones that regulate the level of glucose in human blood (carbohydrate metabolism)
insulin
glucagon
epinephrine
what is the structure of insulin
peptide
in most mammalian cells metabolic reactions occur either of these two places
cytosol or mitochondrial matrix
transport of lactate from muscle to liver
cori cycle
pyruvated is transaminated and the product is transporded from the muscle to the liver
glucose-alanine cycle
In the cori cycle this occurs in the liver
gluconeogenesis
in the glucose-alanine cylce this occurs in the liver, and this occurs in the muscle cell
glucogenogenesis
transamination
acts on muscle tissue to raise glucose levels when needed
epinephrine
acts on the liver, also increases the glucose availability
glucagon
this triggers the feedback response in carbohydrate metabolism
insulin
this appears to be a glucose sensor triggering insulin release
glucokinase
at physiological conditions this enzyme is saturated
hexokinase
This is released in response to glucose
insulin
Alpha adrenergic receptors are located here
liver
beta adrenergic receptors are located here
liver and muscles
Alpha and beta adrenergic receptors bind this hormone
epinephrine
When glucagon and epinephrine are bound to their receptors this occurs
protein kinase A is active and starts glycogen degradation
Epinephirne binding to the alpha adrenrgic receptor on the liver activates this enzyme which does this to the insulin receptor
protein kinase C
inhibits the insulin receptor and stops glycogen synthesis
This promotes fuel use and storage
insulin
glucose is transported into the muslce and adipose tissue via
GLUT 4 glucose transporters
Insulin stimulates glycogen synthesis in liver by doing this
causing dephosphorylation of glycogen synthase
insulin trigers vesicle fusion to the plasma membrane to make this transporter protein present on the cell surface
GLUT 4
Two subunits of insulin receptor and where are they located
Alpha and beta
alpha is a peripheral membrane protein on the outside of the membrane
beta is a trans membrane protein
This residues on the B subunit of the insulin receptor
tyrosine
Tyrosin residues do this to the target proteins called insulin receptor substrates
phosphorylate
T/F: insulin signaling also impacts glycogen-metabolizing enzymes
t
this catalyzes the initial step in glycogen breakdown
glycogen phosphorylase
glucagon is synthesized and released when blood glucose concentrations drop below
5 mM
these two hormones trigger fuel metabolism
glucagon
epinephrine
secreted by alpha cells of pancreas
glucagon
only this organ has glucagon receptors
liver
elevated glucagon is associated with
starving tissues
Glucagon acts through this to phosphroylate two enzymes
cAMP
also called adrenalin
epinephrine
epinephrine is structurally related to
tyrosine
in addtion to increaseing levels of glucose in the blood, glycolysis in muscle cells epinephrine does this
breakdown of fatty acids for energy
protein kinase c does this to insuin receptors casing to them to bind insulin poorly
phosphorylates
glycogen synthase does this
inhibits glycogen synthesis
glycogen phosphorylase does this
promotes glycogenolysis
this acts as a fuel sensor
AMP-dependent protein kinase
the body generates these two compounds whn starving
glucose and ketone bodies
this hormone may establish the human body’s set point
leptin
type 1 diabetes is this type of disease
autoimmune disease
type 2 diabetes is
the body does not respond to insulin
excess glucose is converted to this
sorbitol
accumulation of sorbitol in the lens leads to this
cataract formation
