Lecture 36 - Integration of Metabolism Flashcards
Which of the following is not a metabolic intermediate that links multiple pathways?
A. Glucose
B. Glucose-6-Phosphate
C. Pyruvate
D. Acetyl-CoA
A. Glucose
Which of the following is NOT an end product of glucose-6-phosphate metabolism?
A. Glycogen
B. Pyruvate
C. Alanine
D. Fatty acids
C. alanine
Which of the following is not a fate of Acetyl-CoA?
A. CO2
B. fatty acids
C. oxaloacetate
D. ketone bodies
C. oxaloacetate
This carries nutrients from the intestine to the liver.
A. hepatic portal vein
B. skeletal muscle
C. adipose tissue
D. liver
A. hepatic portal vein
This processes many metabolites, stores glucose, and produces urea. A. hepatic portal vein B. skeletal muscle C. adipose tissue D. liver
D. liver
This uses ATP for mechanical work
A. hepatic portal vein
B. skeletal muscle
C. adipose tissue
D. liver
B. skeletal muscle
This synthesizes, stores, and mobilizes triacylglycerols.
A. hepatic portal vein
B. skeletal muscle
C. adipose tissue
D. liver
C. adipose tissue
This metabolic player is the “sensor” of our diet. It metabolizes nutrients, maintains nutrient levels in blood, processes waste, and synthesizes/secretes plasma proteins.
A. hepatic portal vein
B. skeletal muscle
C. adipose tissue
D. liver
D. liver
The liver primary relies on ___ for its own energy needs.
A. Glycogen
B. Beta-oxidation of fatty acids
C. glucose
D. ketone bodies
B. beta-oxidation of fatty acids
Which of the following is false about metabolism of the liver?
A. it processes most, but not all, dietary amino acids
B. the presence of G-6-Pase makes the liver uniquely able to release glucose from glycogen.
C. It synthesizes most of the urea produced in the body
D. It normally fuels the body by releasing its fat stores during fasting
E. One of its major jobs is to provide fuels for the brain
D. It normally fuels the body by releasing its fat stores during fasting
Adipocytes release triglycerides in response to _____.
A. glucagon/epinephrine
B. low blood sugar
C. insulin
A. glucagon/epinephrine
Fatty acids are transported via _____ in blood.
albumin
ATP is used for _____ needs.
A. immediate
B. short-term
C. long-term
A. immediate
In short bursts of heavy activity, ATP is exhausted in ______.
A. 10 seconds
B. 1-2 minutes
C. over 30 minutes
D. 1-2 seconds
D. 1-2 secodns
_____ is used to reconstitute ATP in anaerobic conditions.
Phosphocreatine
Glycogen is cleaved and metabolized to ____ in anaerobic conditions.
A. pyruvate
B. alanine
C. lactate
C. lactate
This major organ is capable of using lactate as a fuel.
heart
The Cori-cycle utilizes the ___ to regenerate glucose from lactate for active muscle.
liver
Though comprising only 2% of body mass, the brain utilizes what percentage of total body oxygen and glucose?
20%
What system would be used by muscle for heavy, short term exercise, such as a long jump?
Anaerobic exercise, producing lactate
Though the heart can utilize lactate for fuel, the heart’s primary source of energy is _____.
A. the beta-oxidation of fatty acids
B. pyruvate
C. ATP from the Kreb’s cycle
D. Glycogen stores
A. the beta-oxidation of fatty acids
With increased blood glucose levels secondary to diabetes, there are many changes to various metabolic pathways. Outline the following in response to increased BGL:
1) The response of cells
2) Glycogen metabolism
3) Glycolysis
4) Fatty acid synthesis
1) More uptake of glucose into the cells
2) Decreased glycogenolysis; increased glycogen synthesis
3) Increased glycolysis/pyruvate production
4) Increased FA synthesis
In high blood glucose levels, insulin triggers a secondary messenger system to increase glucose utilization and synthesize glycogen. What type of receptor is the insulin receptor?
Tyrosine-kinase receptor
Epinephrine can be released in response to multiple sensory inputs. This includes fright, exercise induced hypoglycemia, etc. What type of receptor is the insulin receptor?
G-protein coupled receptor
Glycogen can be released in response to multiple sensory inputs. This includes fright, exercise induced hypoglycemia, etc. What type of receptor is the glycogen receptor?
G-protein coupled receptor
In the presence of insulin, the well-fed liver will undergo the production of all of the following except:
a. acetyl-CoA through glycolysis
b. TAGs through TAG synthesis
c. Glucose through glycogenolysis
d. Cholesterol synthesis
c. Glucose through glycogenolysis
In well fed muscle, glucose is shunted toward the (glycolysis/glycogenesis) pathway.
glycogenesis
Glucose and amino acids are transported to the liver by ______.
a. chylomicrons
b. the portal vein
c. LDL
b. the portal vein
In the presence of both glucagon or epinephrine in the fasting liver, which of the following will be down-regulated?
A. glyconeogenesis
b. gluconeogenesis
c. glycolysis
d. glycogenolysis
a. glyconeogenesis
In response to glucagon/epinephrine, adipocytes will ______ beta oxidation of fatty acids.
increase
In fasting muscle, beta oxidation will occur in response to epinephrine. What other fuel molecule is used?
ketone bodies from the liver
Glucose is cleaved from glycogen in a liver in the (extended/early) fasting state.
early
What type of metabolism is undergone by tissues in long-term exercise?
oxidative phosphorylation
In the extended fasting state, the liver utilizes all pathways of metabolism except?
A. gluconeogenesis
B. formation of pyruvate from amino acids
c. release of fatty acids from adipocytes
d. glyconeogenesis
d. glyconeognesis
Excess energy in the form of increased alcohol digestion will increase NADH production and leads to _____.
fatty liver disease
Why is “fatty liver” a byproduct of alcohol metabolism?
Tri-acylglycerides are produced from the metabolism of alcohol in the mitochondrial matrix
This functions as the “cellular energy sensory.” It is responsible for the phosphorylation of proteins that control glycogen degradation/synthesis, glucose metabolism, beta-oxidation of fatty acids, etc.
AMP activated protein kinase (AMPK)
How is AMPK activated?
By the presence of low ATP/high AMP
What one organ is highly reliant upon AMPK activity?
brain
Leptin is released during ____ metabolism, and signals that one is full/satisfied.
fat
What region of the body does leptin act upon?
hypothalamus
Insulin disruption is believed to occur in obesity. In leptin resistance, _____ interferes the transduction of leptin binding to the receptor. This ultimately causes a person to remain “hungry,” and overeat.
SOCS (supressors of cytokine signalling)
This is an NAD+ dependent de-acetylase. When active, acetyl groups are cleaved from proteins. This results in high NADH levels, signalling high energy in the cell.
Sirtuin 1
????? I’m confused here
Regarding major metabolic pathways (glycolysis, gluconeogenesis, metabolism of fats, etc.), which organ is capable of carrying them out?
A. Brain
B. Skeletal muscle
C. Liver
D. intestine
C. Liver
The well fed liver relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
a. fatty acids
The fasting liver relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
C. glucose (via gluconeogenesis)
The well fed heart relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
A. fatty acids
The fasting heart relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
B. lactate
The well fed muscle relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
C. glucose
The fasting heart relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
B. Lactate
The well fed brain relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
C. glucose
The early starving brain relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
C. glucose (via gluconeogenesis)
The late starving brain relies on _________ for fuel.
A. Fatty acids
B. Lactate
C. Glucose
D. Ketone bodies
D. ketone bodies
