Biochem II Final Flashcards
________ is the short term (acute) fight or flight hormone
A. Cortisol
B. Epinephrine
C. Insulin
D. Glucagon
B. Epinephrine
Which hormone enters the cell and regulates gene expression?
A. Insulin
B. Glucagon
C. Epinephrine
D. Cortisol
Cortisol
Which second messenger is produced in the cell when glucagon binds to a receptor?
A. CAMP
B. CGTP
C. Inositol-tri phosphate
A. CAMP
NAD+ has an activating effect on _________
A. Malate dehydrogenase
B. Succinate Dehydrogenase
C.Fumarase
D. Aconitase
E. Pyruvate Dehydrogenase
E. Pyruvate Dehydrogenase
______ inhibits a-ketogluatarate dehydrogenase
A. Ca2+
B. NADH
C. CoA
D. ADP
E. Insulin
B. NADH
The activity of the electron transport chain is promoted by ___________
A. Glucose
B. H20
C. ADP
D. CO2
E. NADH
C. ADP
The mechanism by which metabolites perform feedback regulation is always
A. Allosteric
B. Phosphorylation
C. Dephosphorylation
D. Competitive
A. Allosteric
Hexokinase I is found in ______ and has a ______ Km than Hexokinase IV
A. Extrahepatic tissue; higher
B. Extrahepatic tissue; lower
C. Liver; Higher
D. Liver;Lower
B. Extrahepatic tissue; lower
Which of the following is an enzyme of gluconeogenesis?
A. Acetyl-CoA carboxylase
B. Pyruvate carboxylase
C. HMG-CoA reductase
D. Glucose 6-phosphatase
B. Pyruvate carboxylase
Which TCA cycle intermediate connect most directly with the urea cycle?
A. Malate and citrate
B. Fumarate and oxaloacetate
C. Oxaloacetate and Succinate
D. Succinate and Malate
B. Fumarate and oxaloacetate
Which of the following enzymes is inhibited by insulin?
A. Glycogen phosphorylase
B. Phosphofructokinase-1
C. Acetyl-CoA carboxylase
D. HMG-CoA reductase
A. Glycogen phosphorylase
Which of the following is a C5 intermediate?
A. Pyruvate
B. Oxaloacetate
C. Alpha-ketoglutarate
D. HMG-CoA
C. Alpha-ketoglutarate
Which of the following is NOT a carbohydrate metabolism enzyme? (2 Possible answers)
A. Pyruvate Kinase
B. Glycogen synthase
C. Hormone-sensitive lipase
D. Phosphofructokinase
E. Glucose 6-phosphate dehydrogenase
A. Pyruvate Kinase, C. Hormone-sensitive lipase
HMG-CoA is the point of divergence of:
A. The ketone and cholesterol catabolism
B. The biosynthetic pathways of ketones and cholesterol
C. Triacylglycerol and phospholipid catabolism
D. The biosynthetic pathways of triacylglycerols and phospholipids
B. The biosynthetic pathways of ketones and cholesterol
What do regulated enzymes have in common?
-Catalyze non-reversible reactions (unidirectional)
-Occur at the beginning/end of cycles OR key intermediates
-Assist in some allosteric regulation
Regulation of enzymes that occur when binding of a molecule to a different location causes a change in enzyme activity
Allosteric
Phosphorylation
Addition of a phosphate group to a molecule by a protein kinase
Dephosphorylation
Removal of a phosphate group from a molecule by hydrolase
Different ways to categorize hormone and give the category
Type of receptor, type of Biomolecules, synthetic path
Insulin Groups
Peptide, Membrane Receptor
Glucagon
Peptide, Membrane Receptor
Epinephrine Groups
Thyrosine, Membrane Receptor
Cortisol Groups
Cholesterol, Nuclear Receptor
What is the approximate homeostatic (blood glucose)
80-100mg/dL or 5mM
Principles of Regulation
Purpose of metabolic pathways, Hemostasis, Feedback Inhibition
Purpose of Metabolic Pathways
Extract energy, store fuels, synthesis of important blocks, eliminate waste
Homeostasis
Maintained by keeping metabolite concentration at steady state
Feedback inhibition
A product will inhibit its own biosynthetic pathway
Peptides
Glucagon and Insulin
Catecholamines
Epinephrine
Steroids
Testosterone
Vitamin D
Comes from Isoprenoids
Nitric Oxide
Comes from arginine
When is insulin released
When blood glucose is elevated
When is glucagon released
When blood glucose is low
When is epinephrine active
During exercise
Vitamin B1
Thiamine
Vitamin B7
Biotin
Vitamin B3
Niacin
Vitamin B5
Pantothenic Acid
Vitamin B6
Pyroxidine
Vitamin B2
Riboflavin
Gluconeogenesis occurs in
Liver
Fermentation occurs in
Skeletal muscle and RBCs
Ketogenesis occurs in
Matrix of mitochondria (Liver)
Beta oxidation occurs in
Mitochondria (liver) and muscles (some)
Glycolysis occurs in
Cytoplasm