Final Exam

Question 1

Different peptide linkages require anywhere from ___ to ____ calories per mole

Answer 1

500 to 5000 calories per mole

Question 2

In terms of the urea cycle, where in the cell does the conversion of ammonia to carbamoyl phosphate and the conversion of carbamoly phophate + ornithine -> citrulline occur?

Answer 2

In the mitochondria

Question 3

In terms of the urea cycle, the formation of arginosuccinate, formation of arginine and fumarate, and the conversion of arginine into urea and ornithine occur at in the cell?

Answer 3

In the cytoplasm

Question 4

Where does the formation of urea occur at in the body?

Answer 4

In the Liver

Question 5

What is the major rate-limiting factor for almost all energy metabolism in the body?

Answer 5

ADP

Question 6

What are the factors that influence metabolic rate?

Answer 6

Arousal vs sleeping
Skeletal muscle
Age
Testosterone
Growth hormone 
Fever
Sleep 
Malnutrition 
Cold

Question 7

What is the best known stimuli for increasing the rate of thyroid stimulating hormone?

Answer 7

Cold

Question 8

What are the vascular inputs of the Liver?

Answer 8

Portal vein and hepatic artery

Question 9

What effect does cirrhosis have on blood flow in the liver?

Answer 9

Cirrhosis increases resistance to blood flow

Question 10

What is the effect of a clot blocking the portal vein or a major branch of the Liver vascular supply?

Answer 10

Blockage of return blog from the spleen and intestines

Increase of capillary pressure in the intestinal wall leads to loss of fluid and eventually death

Question 11

What could a higher than normal back pressure in hepatic veins lead to?

Answer 11

Ascities (accumulation of fluid in the abdominal cavity)

Question 12

What are the functions of the liver?

Answer 12

Carb metabolism 
Fat metabolism 
Vitamin storage 
Protein metabolism 
Formation of coagulation factors 
Removal or excretion of drugs, hormones and other substances

Question 13

Stores of glucose as glycogen, conversion of galactose and fructose to glucose, gluconeogenesis and release of stored glucose into the circaultion are all examples of what function of the liver?

Answer 13

carbohydrate metabolism

Question 14

Oxidation of fatty acids for energy
synthesis of cholesterol, phospholipids and lipoproteins
Synthesis of fats from proteins and carbs

Are all examples of what function of the liver?

Answer 14

Fat metabolism

Question 15

What vitamins does the liver store?

Answer 15

Vitamins A, D and B12

Question 16

Deamination of amino acids
Formation of urea
Formation of plasma proteins
Interconversions of various amino acids

Are all a part of what funciton of the liver?

Answer 16

Protein metabolism

Question 17

What coagulation factors are formed in the liver?

Answer 17

Fibrinogen
Prothrombin
Accelerator globulin
Factors VII, IX, and X

Question 18

Detoxifies or excretes into the bile: sulfonamides, penicillin, ampicillin and erythromyocin
Excretes excess calcium into the bile
Detoxification and removal of ammonia and ethanol

Are all components of what function of the liver?

Answer 18

Removal or excretion of drugs, hormones and other substances

Question 19

During Bilirtubin formation all of these steps occur where?
Hb phagocytized by macrophages
Split into globin and heme
Heme ring is opened to free Iron
Heme is transported in the blood by transferrin
Straight chain of pyrrole nuclei is formed
Heme is converted by heme oxygenate into biliverdin
Biliverdin is converted to free (unconjugated) bilirubin

Answer 19

The reticuloendothelial system

Question 20

What transports heme in the blood?

Answer 20

Transferrin

Question 21

Heme is converted by heme oxygenate into what?

Answer 21

Biliverdin

Question 22

How is free bilirubin transported in the blood stream and what is its destination?

Answer 22

Attached to plasma albumin to liver hepatocytes

Question 23

In bilirubin formation, what happens in the liver?

Answer 23

Free bilirubin is released from plasma albumin within the liver cells and conjugated

Question 24

In bilirubin formation, Hb is released from damaged red blood cells and enters what system?

Answer 24

Reticuloendothelial system

Question 25

What can the free bilirubin be conjugated with in the liver?

Answer 25

Glucuronic acid to form bilirubin glucuronids (80%)

Sulfate to form bilirubin sulfate (10%)

Variety of other substances (10%)

Question 26

What two things happen to conjugated bilirubin?

Answer 26

Secreted via active transport into the intestine

OR

Excreted into the urine

Question 27

If the conjugated bilirubin goes to the small intestine, where does it get converted to urobilinogen via bacterial action?

Answer 27

Terminal Ileum

Question 28

Where does the oxidation of the urobilinogen to form Urobilin and Stercobilin?

Answer 28

Colon

Question 29

What components are typically excreted in the feces?

Answer 29

Urobilin and Stercobilin

Question 30

Urobilinogen can go down two pathways, what are those?

Answer 30

Either undergo oxidation to form urobilin and stercobilin

OR

Enter the enterohepatic circulation and return to the liver where it is re excreted by the liver OR excreted in the urine

Question 31

What are the effects of insulin on fat storage?

Answer 31

Promotes conversion of excess glucose into FA

Decreases utilization of fat

Plays a critical role in fat storage