Structure Of Carbohydrates And Carbohydrate Metabolism

Question 1

What is needed to activate the glucose transporters in adipose tissues and striated muscles?

Answer 1

Insulin

Question 2

Which glucose transporter is activated on an insulin-dependent mechanism?

Answer 2

GLUT4 transporters

Question 3

Which glucose transporter facilitates the absorption of fructose?

Answer 3

GLUT5 transporters

Question 4

What are the glucose transporters that require sodium-dependent active uptake of glucose against a concentration gradient?

Answer 4

SGLT1/2 transporters

Question 5

What vitamins are essential in the citric acid cycle?

Answer 5

Vitamin B1, Vitamin B2, Vitamin B3, Vitamin B5

Question 6

What are the processes that replenish the intermediates of the citric acid cycle called?

Answer 6

Anaplerotic reactions

Question 7

Which enzyme is important in maintaining the adequate concentration of oxaloacetate in the citric acid cycle?

Answer 7

Pyruvate carboxylase

Question 8

What are the major sites of gluconeogenesis in the body?

Answer 8

Liver (90%), Kidney (10%)

Question 9

What process occurs when lactate formed by glycolysis in skeletal muscle is transported to the liver?

Answer 9

Cori cycle

Question 10

This substance is important in the attachment of glucose to the glycogen substrate

Answer 10

Uridine diphosphate

Question 11

It serves as a primer for glycogen synthesis when glycogen is completely depleted

Answer 11

. glycogenin

Question 12

What enzyme is deficient in Von Gierke disease?

Answer 12

Glucose-6-phosphatase.

Question 13

What enzyme is deficient in Pompe disease?

Answer 13

Lysosomal acid maltase.

Question 14

What enzyme is deficient in Cori disease?

Answer 14

Debranching enzyme.

Question 15

What enzyme is deficient in Andersen disease?

Answer 15

Branching enzyme.

Question 16

What enzyme is deficient in McArdle syndrome?

Answer 16

Muscle phosphorylase.

Question 17

What enzyme is deficient in Hers disease?

Answer 17

Liver phosphorylase.

Question 18

What enzyme is deficient in essential fructosuria?

Answer 18

Fructokinase.

Question 19

What enzyme is deficient in hereditary fructose intolerance?

Answer 19

Aldolase B.

Question 20

What enzyme is lacking in the retina, lens, kidneys, and Schwann cells in uncontrolled diabetes?

Answer 20

Sorbitol dehydrogenase.

Question 21

This pentose is increased in the urine of patients with essential pentosuria?

Answer 21

Xylulose.

Question 22

What is the most common disease producing enzyme abnormality in humans?

Answer 22

Glucose-6-phosphate dehydrogenase deficiency.

Question 23

Altered hemoglobin precipitating in the red blood cells of patients with G6PD deficiency.

Answer 23

Heinz bodies

Question 24

These are abnormally shaped red blood cells occurring due to the phagocytic removal of Heinz bodies in the spleen

Answer 24

Degmacytes (Bite Cells)

Question 25

What is deficient in chronic granulomatous disease?

Answer 25

NADPH oxidase. ## Footnote It leads to severe, persistent, and chronic pyogenic infections caused by catalase-positive bacteria.

Question 26

What is the most abundant organic molecule in nature?

Answer 26

Carbohydrates

Question 27

What is the main storage form of carbohydrates in humans?

Answer 27

Glycogen

Question 28

What is the building block of all carbohydrates?

Answer 28

Monosaccharides

Question 29

What bond links sugar units or monosaccharides together?

Answer 29

Glycosidic bonds

Question 30

What is the most predominant sugar in the human body?

Answer 30

Glucose ## Footnote Universal fuel of fetus

Question 31

Which tissues use glucose as their main metabolic fuel?

Answer 31

Brain, Renal medulla, Cornea, Retina, Testis, RBCs

Question 32

What is the major constituent of starch?

Answer 32

Amylopectin

Question 33

What is the most stable conformation of glucose?

Answer 33

Chair conformation

Question 34

What are common non-reducing sugars?

Answer 34

Sucrose, Trehalose

Question 35

What is the 2nd epimer of glucose?

Answer 35

Mannose

Question 36

What is the 3rd epimer of glucose?

Answer 36

Allose

Question 37

What is the 4th epimer of glucose?

Answer 37

Galactose

Question 38

What is the more common enantiomer of carbohydrates?

Answer 38

D-isomer

Question 39

Which glucose transporter requires insulin?

Answer 39

GLUT4 ## Footnote This is the only transporter that requires insulin (insulin-dependent)

Question 40

All glucose transporters utilize facilitated diffusion, except for this transporters) which use(s) secondary active transport

Answer 40

SGLT1/2

Question 41

This glucose transporter allows the transport of fructose

Answer 41

GLUT5

Question 42

This carbohydrate is responsible for sperm motility

Answer 42

Fructose