BCH 351 Exam 3-Questions With 100%
Verified Answers.
Adenylyl cylcase convers ATP to PP1 and cAMP (later activates pka) - ✔✔describe the
signal transduction pathway in terms of molecules
Hormone binds to and activates a stimulatory receptor (Rs).
Rs activates a stimulatory G protein (Gas)-GTP.
Gas-GTP activates adenylyl cyclase which synthesizes cAMP(5',3' AMP).
cAMPbinds protein kinase A (PKA); this releases C subunits from R subunits and PKA is
activated.
PKA phosphorylates target proteins (transcription factors) at Ser Thr, activating them
- ✔✔describe activation pathway
Option 1: The alpha subunit has the ability to self-hydrolyze GTP into GDP, causing the
alpha subunit to dissociate from adenylyl cyclase, causing adenylyl cyclase to be inactive.
Option 2: Cyclic AMP can be converted into 5'-AMP via the enzyme phosphodiesterase -
✔✔how is the signal transduction pathway turned off
,adenylyl cyclase cyclizes ATP to cAMP - ✔✔how is the signal transduction pathway
turned on
insulin and growth factors (epidermal and fibroblast) - ✔✔what hormones does
receptor tyrosine kinase use
ligand binds to receptor
dimerization - signal transduction. requires lateral movement through the membrane.
autophosphorylation - effector enzyme - ✔✔describe receptor tyrosine kinase pathway
insulin and glucagon - ✔✔hormones that regulate the breakdown and synthesis of glycogen
They will bind to membrane protein receptors to initiate a signaling cascade - ✔✔how do
insulin and glucagon regulate the breakdown and synthesis of glycogen
eating = insulin increased and glucaon decreased
fasting = glucagon increased and insulin decreased - ✔✔Immediately after eating,
will glucagon or insulin be more active? What about during fasting?
insulin - ✔✔what promotes glycogenesis
process of glycogen synthesis and storage - ✔✔what is glycogenesis
glucogon - ✔✔what promotes glycogenolysis
break down of glycogen into glucose - ✔✔what is glycogenolysis
, glycogen phosphorylase - ✔✔used to break down glycogen
glycogen synthase - ✔✔used to synthesize glycogen
Insulin activates glycogen synthase
Glycogen synthase is used to create more glycogen to be stored when glucose is very
abundant in the body.
turns off phosphorylase - ✔✔which hormone molecule would activate the synthase?
what does it turn off
Phosphorylation activates glycogen phosphorylase
active - ✔✔When phosphorylated, will glycogen phosphorylase be active or inactive?
glucagon activates glycogen phosphorylase.
Glycogen phosphorylase will break down glycogen into glucose-1-phosphate, which can be later
converted and used in glycolysis.
turns of synthase - ✔✔which hormone molecule would activate the phosphorylase
what does it turn off
glucagon promotes phosphorylation and insulin promotes dephosphorylation -
✔✔which hormone promotes phosphorylation and dephosphorylation
Verified Answers.
Adenylyl cylcase convers ATP to PP1 and cAMP (later activates pka) - ✔✔describe the
signal transduction pathway in terms of molecules
Hormone binds to and activates a stimulatory receptor (Rs).
Rs activates a stimulatory G protein (Gas)-GTP.
Gas-GTP activates adenylyl cyclase which synthesizes cAMP(5',3' AMP).
cAMPbinds protein kinase A (PKA); this releases C subunits from R subunits and PKA is
activated.
PKA phosphorylates target proteins (transcription factors) at Ser Thr, activating them
- ✔✔describe activation pathway
Option 1: The alpha subunit has the ability to self-hydrolyze GTP into GDP, causing the
alpha subunit to dissociate from adenylyl cyclase, causing adenylyl cyclase to be inactive.
Option 2: Cyclic AMP can be converted into 5'-AMP via the enzyme phosphodiesterase -
✔✔how is the signal transduction pathway turned off
,adenylyl cyclase cyclizes ATP to cAMP - ✔✔how is the signal transduction pathway
turned on
insulin and growth factors (epidermal and fibroblast) - ✔✔what hormones does
receptor tyrosine kinase use
ligand binds to receptor
dimerization - signal transduction. requires lateral movement through the membrane.
autophosphorylation - effector enzyme - ✔✔describe receptor tyrosine kinase pathway
insulin and glucagon - ✔✔hormones that regulate the breakdown and synthesis of glycogen
They will bind to membrane protein receptors to initiate a signaling cascade - ✔✔how do
insulin and glucagon regulate the breakdown and synthesis of glycogen
eating = insulin increased and glucaon decreased
fasting = glucagon increased and insulin decreased - ✔✔Immediately after eating,
will glucagon or insulin be more active? What about during fasting?
insulin - ✔✔what promotes glycogenesis
process of glycogen synthesis and storage - ✔✔what is glycogenesis
glucogon - ✔✔what promotes glycogenolysis
break down of glycogen into glucose - ✔✔what is glycogenolysis
, glycogen phosphorylase - ✔✔used to break down glycogen
glycogen synthase - ✔✔used to synthesize glycogen
Insulin activates glycogen synthase
Glycogen synthase is used to create more glycogen to be stored when glucose is very
abundant in the body.
turns off phosphorylase - ✔✔which hormone molecule would activate the synthase?
what does it turn off
Phosphorylation activates glycogen phosphorylase
active - ✔✔When phosphorylated, will glycogen phosphorylase be active or inactive?
glucagon activates glycogen phosphorylase.
Glycogen phosphorylase will break down glycogen into glucose-1-phosphate, which can be later
converted and used in glycolysis.
turns of synthase - ✔✔which hormone molecule would activate the phosphorylase
what does it turn off
glucagon promotes phosphorylation and insulin promotes dephosphorylation -
✔✔which hormone promotes phosphorylation and dephosphorylation
