Exam 2 Flashcards
What is the role of cAMP?
The premise is false; cAMP is not an enzyme
-NOT an enzyme, but a secondary messenger inside the cell that activates enzymes; function based on the strength of signal from insulin or epinephrine
PDH
- Only exists inside the mitochondria
- Contains two components and performing two actions on pyruvate
- Regulation of PDH is critical in maintaining plasma [GLU]
A cell can obtain as much energy from an Acetyl-CoA molecule as it can from a Pyruvate molecule. T/F?
True - 1 Pyruvate molecule yields you 1 Acetyl-CoA molecules utilizing the enzyme PDH. Therefore you get as much energy from a Pyruvate
If cells can obtain all of their ATP energy from carbohydrate, and if cells can obtain all of their ATP energy from protein, why can’t cells obtain all of their ATP energy from fat?
*Because oxaloacetate cannot be generated from fat
Which is the rate limiting step in the TCA cycle? A. Malate B. Oxaloacetate C. PDH concentration D. Citrate
B. Oxaloacetate
Products of the TCA Cycle include each of the following except. A. NADH B. H+ C. CO2 D. NAD+ E. FADH2
D. NAD+
-NAD+ is being reduced to produce NADH + H+ which in turn go through the ETC
TCA Cycle
-Requires BOTH oxygen and a working mitochondria
-Lipids only have a limited yet powerful role.
Fats are pound for pound far more energy packed
-Oxaloacetate is critical in burning Acetyl-CoA
Why during starvation protein and carb resources are devoted to production of oxaloacetate and glucose.
-Intermediates —-> Glucose via gluconeogenesis!!
TCA Downside
-CO2 is constantly produced
-H2O is not only utilized but produced
-Always remember that CO2 in an aqueous environment is an acid
So what happens to cells as they produce energy?
They become more acidid —> Will learn more about this in acid-base
Purpose of Gluconeogenesis is to produce glucose from non-carbohyrdates. T/F?
True - Gluconeogenic substrates (all non carbohydrates) G – Glycerol L – Lactate A – Amino Acids P – Proprionic Acid
Gluconeogenesis is performed by running the glycolytic pathway backwards. T/F?
False
What are your Gluconeogenic substrates?
GLAP: G - Glycerol L - Lactate A - Amino Acids P - Propionic Acid
Gluconeogenesis doesn’t require energy because it’s purpose is to create energy. T/F?
False
What is the main form of lipid storage in the body? A. Fat B. FFA C. VLDL D. LDL
A. Fat
-Fat = TAG
TAG is absorbed through the GI Tract. T/F?
False - TAG’s are broken down into free fatty acids which in turn are absorbed than made into a molecule called Chylomicron.
VFA in ruminants are bound by plasma protein. T/F?
False
FFA are largely not bound by plasma protein. T/F?
False - FFA circulate in usually a 99:1 bound to unbound ratio
Who produces Chylomicrons?
Small intestine
Who produces VLDL?
Liver
A client comes up to you and says she heard the news talking about how cholesterol is bad and causing heart attacks. She hears from a friend that dogs have cholesterol in their blood. And is now worried her little Queen Elizabeth will have problems. You tell her not to worry because cholesterol is always found in the body and is important. T/F?
True
What is the function of LPL?
- Lipoprotein Lipase (LPL)
- Breaks down TAG into MG + 2 FFA; allows movement from plasma into cells
What is the function of HSL?
- Hormone Sensitive Lipase (HSL)
- Breaks down stored fat (lipolysis) between meals so it can leave cells
- Release of cholesterol from cholesterol ester for steroid production
Who is a major influence on LPL and HSL?
Insulin
+LPL/-HSL @ Adipose tissue
-LPL @ Skeletal muscle
Which organ does not like to store fat?
A. Liver
B. Skeletal Muscle
C. Adipose Tissue
A. Liver
-Liver does not like to store fat but instead package it into VLDL and ship it out to other organs for storage. Fat stores accumulating in the liver leads to a condition known as Fatty Liver Disease.
What is the major function of Ketones?
A. Molecule composed of waste molecules for the body to rid.
B. Provide energy to various cells
C. Substrate for gluconeogenesis
D. Dangerous byproduct of lipid metabolism
B. Provide energy to various cells
*Double check answer
You are a new clinician right out of school and an owner comes in saying their dog smells like he drank a bottle of Nail polish remover. Because you were not able to forget your Reich lectures you know that what is going on in this dog.
A. Liver damage
B. Starvation
C. Increased lipolysis
D. Skeletal muscle releasing ketones into the body
E. Dog got into the owners nail polish remover
C. Increased Lipolysis
Beta Oxidation
-Obtaining Acetyl-CoA from an X- carbon FFA
-Stops at Proprionic Acid (3 carbon molecule)
In turn used in gluconeogenesis
-Requires activation via Acetyl-CoA synthase
-Can’t do anything unless you stick a CoA on it (see this again in fatty acid synthesis.
-Must occur in mitochondria despite beginning in cytoplasm
When is plasma [Glucagon] zero in a dog?
The premise is false; [Glucagon] are never zero
Insulin potently inhibits hepatic glycogenolysis and lipolysis within adipocytes; Glucagon potently promotes hepatic glycogenolysis and lipolysis within adipocytes. T/F?
True
How many Acetyl-CoA can you can get from a 23-Carbon Fatty Acid via beta-oxidation?
A. Premise is false; Fatty Acids don’t get this long.
B. 1
C. 10
D. 11
E. 23
C. 10
The purpose of lipolysis is to put TAG into the bloodstream for use during periods of malnutrition. T/F?
False
After 3 days of not eating where is an animal getting most of it’s energy?
A. Stored glucose pack in glycogen
B. Stored amino acids packed in muscle
C. Stored TAG stored in adipose tissue
C. Stored TAG stored in adipose tissue
Adipose tissue doesn’t uptake glucose because it doesn’t have a need for it. T/F?
False
How do animals get essential fatty acids? A. Diet B. Hepatocytes C. Adipose tissue D. GI tract microbes
A. Diet
Which of the following is not a source of a gluconeogenic substrate: A. Glycerol B. 17 carbon fatty acid C. Lactic acid D. Alpha-Ketogluterate E. Acetyl Coa
E. Acetyl CoA
Which of the following is NOT commonly found in the plasma of domestic animals? A. Triacylglyccerol B. Free fatty acid C. Volatile fatty acid D. Acetyl CoA E. Ketone
D. Acetyl CoA
Ketone bodies are not dangerous because they can’t spontaneously become Acetone. T/F?
True
Which of the following does Malonyl-CoA inhibit? A. Carnitine acyltransferase B. Insulin C. LPL D. Glucokinase E. Glycogen synthase
A. Caritine acyltransferase
Which of the follow produce glucose?
A. Hepatocytes
B. Hepatocytes, Proximal tubule cells of kidney
C. Heptaocytes, Proximal tubule cells of kidney, Sm. Intestinal cells
D. Heptaocytes, Proximal tubule cells of kidney, Sm. Intestinal cells, Adipose tissue
B. Hepatocytes, Proximal tubule cells of kidney
The lymphatic system is how VLDL get into plasma. T/F?
False
Gluconeogenesis is an ATP requiring pathway. From what does the liver of a fasting animal obtain MOST of this ATP? A. Liver glycogen B. Muscle glycogen C. Ketone D. Adipose fatty acid
D. Adipose fatty acid
Where primarily does the glucose circulating in a wild cats blood come from? A. Last meal still being absorbed B. Hepatocyte glycogen C. Gluconeogenesis D. Skeletal muscle glycogen
C. Gluconeogenesis
Which of the following promote fat synthesis at the liver? A. Insulin B. Growth hormone C. Epinephrine D. Glucagon
A. Insulin
Right after a meal the insulin:glucagon ration in dogs is greater than the insulin:glucagon ratio in cats. T/F?
True
What can the body do with Malonyl-CoA? A. Gluconeogenesis B. Protein synthesis C. Fatty acid synthesis D. Anything it wants E. Nothing it’s a waste product.
C. Fatty acid synthesis
Who in the body exports TAGs?
A. Liver
B. Liver, Adipose tissue
C. Liver, Adipose tissue, Sm. Intestine
D. Liver, Adipose tissue, Sm. Intestine, muscle
E. Liver, Adipose tissue, Sm. Intestine, muscle, Lg. Intestine.
C. Liver, Adipose tissue, Sm. Intestine
Acetyl-Co Carboxylase is an important enzyme in the breakdown of fatty acids. T/F?
False
When is the CAT system the most active? A. Just after a meal B. 12 hours after a meal C. 24 hours after a meal D. 48 hours after a meal
???
Adipocytes use glycerol in the synthesis of glucose. T/F?
False
Chylomicrons contain protein. T/F?
True
Which cells utilize lots of ketones: A. Hepatocytes B. Neurons C. RBC's D. Muscle E. Adipose
???
VLDL are largely composed of ingested triacylglycerol. T/F?
False
What is the most abundant molecule found in VLDL? A. TAG B. Cholesterol C. Vitamins D. Phospholipid E. Monoacylglycerol
TAG
What is the most abundant lipid in the cow following a meal? A. Acetic Acid B. TAG C. Phospholipid D. Sphingolipid E. Monoacylglycerol
A. Acetic Acid
Insulin post meal promotes an increase in glucose ports in which of the following cells? A. Neurons B. RBC's C. Hepatocytes D. Skeletal Muscle
D. Skeletal Muscle
When do cells stop utilizing glucose?
A. When glucose is plentiful
B. When glucose levels are low
C. When lots of acetyl-CoA are being produced from lipolysis
D. The premise is false, cells never stop utilizing glucose.
???
Adipose tissue’s energy demands are so low they don’t require ATP all the time. T/F?
False
Ketones can be detected without any veterinary tests. T/F?
True
Which is a target for LPL? A. MAG in plasma B. TAG in VLDL C. TAG in lumen of sm. Intestine D. TAG in adipose tissue E. TAG in muscle cells
B. TAG in VLDL
The body can store excess carbohyrdates in adipose tissue. T/F?
True
Plants don’t contain TAG. T/F?
False
- Which of the following statements is TRUE?
a) insulin promotes glycogenesis and epinephrine promotes glycogenesis
b) insulin promotes glycogenesis and epinephrine inhibits glycogenesis
c) insulin inhibits glycogenesis and epinephrine promotes glycogenesis
d) insulin inhibits glycogenesis and epinephrine inhibits glycogenesis
B. insulin promotes glycogenesis and epinephrine inhibits glycogenesis
- What is so important about pyruvate dehydrogenase kinase?
a) it oxidizes kinases
b) it reduces kinases c) it produces NADH
d) it produces NAD+
e) it controls the activity of pyruvate dehydrogenase
E. it controls the activity of pyruvate dehydrogenase
- What happens to most of the citrate in a normal functioning mitochondria?
a) the premise is false; citrate is not normally found in mitochondria
b) it is oxidized and carboxylated
c) it is reduced and carboxylated
d) it is reduced and decarboxylated
e) it is oxidized and decarboxylated
E. it is oxidized and deacrboxylated
- Gluconeogenic substrates include each of the following EXCEPT:
a) fructose
b) propionate
c) amino acid
d) lactate
e) glycerol
A. Fructose
- Compared to the amount of ATP normally generated by a cell through the normal oxidation of glucose, how much ATP would be generated by the cell if glucose were placed directly into the cell’s mitochondria?
a) much more
b) more
c) the same amount
d) less
e) much less
E. much less
- An animal has not eaten in a week, but its plasma [glucose] is now 60% of what it was shortly after it had last eaten. Where is the glucose coming from now?
a) it isn’t coming from anywhere; it is normal to have this much ingested glucose circulating in plasma one week after the last meal
b) glycogenolysis in muscle
c) glycogenolysis in liver
d) gluconeogenesis in liver
e) the pancreas
D. gluconeogenesis in liver
- Where does most gluconeogenesis occur?
a) liver
b) small intestine
c) kidney
d) fat cells
e) muscle cells
A. liver
- Which of the following lipids serves no useful purpose?
a) the premise is false; all of the following lipids serve useful purpose
b) cholesterol
c) fatty acids
d) propionate
e) ketones
A. the premise is false; all of the following lipids serve useful purpose
- What happens to ingested fat in the lumen of the gastrointestinal tract?
a) it is oxidized
b) it is hydrolyzed
c) it is oxidized and converted into acetyl CoA molecules
d) it is hydrolyzed and converted into acetyl CoA molecules
e) it is hydrolyzed, oxidized and converted into acetyl CoA molecules
B. it is hydrolyzed
- Prostaglandins are valuable for each of the following reasons EXCEPT:
a) they can be converted into fatty acids and oxidized as fuel
b) they promote destruction of the corpus luteum in animals that have ovulated but who are not pregnant
c) they promote cell repair
d) they promote inflammation
e) they promote the clotting of blood
A. they can be converted into fatty acids and oxidized as fuel
- Various lipids are found in plasma, but their concentrations vary throughout the day. Which of the following statements concerning these concentrations is TRUE?
a) [FFA] tends to be higher long after the last meal and [ketone] tends to be higher long after the last meal
b) [VLDL] tends to be higher long after the last meal and [ketone] tends to be lower long after the last meal
c) [chylomicron] tends to be higher long after the last meal and [ketone] tends to be higher long after the last meal
d) [FFA] tends to be lower right after the last meal and [chylomicron] tends to be higher long after the last meal
e) [FFA] is low at all times
A. [FFA] tends to be higher long after the last meal and [ketone] tends to be higher long after the last meal
- Which of the following BEST DESCRIBES insulin effect at adipose tissue?
a) insulin promotes LPL activity and promotes HSL activity
b) insulin promotes LPL activity and inhibits HSL activity
c) insulin inhibits LPL activity and promotes HSL activity
d) insulin inhibits LPL activity and inhibits HSL activity
B. insulin promotes LPL activity and inhibits HSL activity
- Complete oxidation of a fatty acid requires which of the following?
a) O2 only
b) O2 and an electron transport chain only
c) O2, an electron transport chain and a functioning CAT system only
d) O2, an electron transport chain, a functioning CAT system and dehydrogenases only
e) O2, an electron transport chain, a functioning CAT system, dehydrogenases and Vitamin C
D. O2, an electron transport chain, a functioning CAT system and dehydrogenases only
*Most oxaloacetate is derived from carbohydrate. T/F?
True
*If the electron transport chain ceases to function in an animal cell, that cell must depend exclusively on glycolysis for its ATP needs. T/F?
True
*At some cells, an increase in thyroid hormone results in decreased ATP production per oxidized NADH and increased heat production per oxidized NADH. T/F?
True
*Once the liver runs out of glycogen, it is stimulated to initiate gluconeogenesis. T/F?
**False, but check this answer
*Lipolysis at adipose tissue begins once the body has run out of glucose. T/F?
False
*Proteolysis begins once the body has run out of stored fat. T/F?
False
*The liver is the major producer of ketone. T/F?
True
*Pyruvate dehydrogenase kinase activity decreases as the concentration of acetyl CoA increases. T/F?
False
*Epinephrine promotes lipolysis. T/F?
True
*Fatty acid cannot be oxidized in the absence of oxaloacetate. T/F?
True
*When there is an overabundance of acetyl CoA in the liver, the acetyl CoA are incorporated into glucose and stored as glycogen in the liver. T/F?
False
*When there is an overabundance of acetyl CoA in the liver, the acetyl CoA are incorporated into fatty acids and stored as fat in the liver. T/F?
False
*When a normally aerobic cell is denied O2, its fatty acids are reduced to lactate. T/F?
False
*An aerobic cell can obtain more ATP from a gram of fat than it can from a gram of glycogen, but an anaerobic cell can obtain more ATP from a gram of glycogen than it can from a gram of fat. T/F?
True
*Prostaglandins are derived from cholesterol. T/F?
False
