Carbohydrates Flashcards Preview

Biochemistry > Carbohydrates > Flashcards

Flashcards in Carbohydrates Deck (39):
1

What are examples of anabolic reactions?

Protein and triglyceride synthesis, glycogenesis

2

What are example of catabolic reactions?

glycolysis, beta-oxidation, glycogenolysis

3

What are example amphibolic pathways?

Citric acid cycle

4

Oxidation of Glucose yields?

Glucoronic acid

5

Reduction of glucose yields?

Sorbitol

6

Ribose: Removal of hydroxyl group at C2 yields?

deoxyribose

7

What is excreted in essential pentosuria?

Xylulose

8

Glucose + Fructose?

Sucrose

9

Glucose + Galactose?

Lactose

10

Glucose + Glucose?

Lactose

11

Bonds of Starch?

alpha-glycosidic

12

Bonds of cellulose?

beta-glycosidic

13

What enzyme deficiency causes hemolytic anemia and is the most common enzyme defect in glycolysis?

Pyruvate kinase

14

What enzyme deficiency causes low exercise capacity especially on high carbohydrate diets?

Muscle phosphofructokinase

15

What enzyme deficiency is the most common cause of congenital lactic acidosis; x linked dominant disease

Pyruvate dehydrogenase

16

TCA intermediates: delivers acetyl coA to cytosol for fatty acid synthesis via citrate shuttle

Citrate

17

TCA intermediates: Used for heme synthesis and activation of ketone bodies in extrahepatic tissues

succinyl coA

18

TCA intermediate: may be used for gluconeogenesis

Malate

19

What is the rate liming step of glycolysis?

phosphofructokinase-1

20

What is the rate limiting step of TCA?

isocitrate -> alpha ketoglutarate (Isocitrate dehydrogenase)

21

What is the rate limiting step of Gluconeogenesis?

Fructose 1,6 bisphosphate -> Fructose 6-phosphate (Fructose 1,6-bisphosphatase)

22

What is the rate limiting step of glycogenesis?

Elongation of glycogen chains (creation of alpha 1,4 glycosidic bond by glycogen synthase)

23

What is the rate limiting step of glycogenolysis?7

Shortening of glycogen chains (Glycogen phosphorylase)

24

What is the coenzyme of glycogen phosphorylase in glycogenolysis?

Pyridoxal phosphate

25

What disease has glucose 6 phoshatase deficiency?

Von Gierke Disease

26

Clinical Features of Von Gierke Disease?

Increase glycogen in liver, hypoglycemia, lactic acidosis, ketosis, hyperlipidemia, hepatomegaly

27

What disease has deficiency in lysosomal acid maltase?

Pompe Disease

28

Clinical Features of Pompe Disease

Increase in glycogen in lysosomes; juvenile onset; hypotonia, death from heart failure by 2 years old; muscle dystrophy (adult onset)

29

What enzyme is deficient in Cori Disease?

Debranching enzyme

30

What is deficient in McArdle syndrome?

Muscle phosphorylase

31

What is an alternative pathway for oxidation of glucose in the liver?

Uronic Acid Pathway

32

An essential component of glycosaminoglycans and is required in detoxifixation reactions of insoluble compounds like bilirubin, steroids, morphine

Glucoronic acid

33

Where does pentose phosphate pathway occur?

RBC and tissues that produce lipids (liver, adipose tissue, adrenals, thyroid, testes, lactating mamaries)

34

What is the rate limiting step of PPP?

Glucose 6 phosphate to 6 phosphogluconate (glucose 6 phosphate dehydrogenase)

35

What catalyzes reduced glutathione removing H2O2?

Glutathione Peroxidase

36

What disease involves decrease in NADPH in RBC and decreased activity of glutathione reductase causing free radicals and peroxidase accumulation?

G6PD deficiency

37

What are the 2 pathologies of G6PD deficiency?

Heinz bodies and Bite cells

38

What disease is caused by deficiency in NADPH oxidase where molecular O2 is converted to superoxide in leukocytes?

Chronic Granulomatous Disease

39

In chronic granulomatous disease, which bacteria is responsible?

catalase positive bacteria