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Flashcards in GI Deck (48):
0

3 irreversible pathways of glycolysis

-hexokinase (1)
-phosphofructokinase (3)
-pyruvate kinase (last)

1

Glycogen synthase primer

Glycogenin (adds 4 glucose to itself)

2

Glucose to glucose-6-phosphate is catalysed by

Hexokinase

3

Glucose-6-phosphate to glucose-1-phosphate and vice versa is catalysed by

Phoshphoglucomutase

4

Glucose-1-phosphate to UDP glucose is catalysed by

UDP glucose phosphorylase

5

Rate limiting enzyme of glycogenesis

Glycogen synthase

6

Enzyme which adds branches to glycogen

Transglycosylase

7

Glycogenolysis catalysed by

Glycogen phosphorylase

8

Processes by which glycogen can be broken down by skeletal muscle

TCA cycle and glycolysis

9

Process by which glycogens broken down by liver

Glycogenolysis

10

How is glucose transported to blood?

GLUT2 transporter

11

The Cori cycle

Lactate-pyruvate-glucose

12

Location of gluconeogenesis

Liver (kidneys)

13

Effects of insulin and starvation on albumin levels?

Insulin increases, starvation decreases. Levels are low in liver disease

14

How can plasma proteins be separated?

Simple electrophoresis

15

What is ceruloplasmin?

Alpha protein

16

What type of protein is retinol binding protein?

Alpha protein, transports vitamin A

17

Function of alpha proteins?

Transport lipoproteins, lipids, hormones and bilirubin

18

Example of a beta protein

Transferrin, transports iron

19

Protein which is the main determinant of plasma oncotic pressure?

Albumin (water soluble and negatively charged)

20

Albumin levels in liver disease?

Low

21

Fatty acids, bilirubin and thyroid hormones are transported by what?

These endogenous lipophilic substances are transported by albumin. Albumin also transports exogenous substances i.e drugs like aspirin

22

How is iron stored in cells?

As ferritin

23

How is copper transported?

Bound to ceruloplasmin. Copper is needed for regulation of redox reactions and for transport/use of iron.

24

Are the steroid hormones and the T3/T4 hormones hydrophilic or hydrophobic?

Hydrophobic

25

How is thyroxine transported?

Thyroid-binding globulin (extended biological half life and increased plasma concentration)

26

How is cortisol transported?

Cortisol-binding globulin (extended biological half-life and increased plasma concentration)

27

Function of chylomicrons?

Transport of exogenous fat to liver

28

Function of VLDL?

Transport of endogenous fat to peripheral tissues

29

Function of IDL?

LDL precursor

30

Function of LDL?

Transport of cholesterol to peripheral tissues

31

Function of HDL?

Reverse cholesterol transport

32

What vitamins and metal can the iron store?

Vitamins A, D and B. Iron (stored associated with Ferritin)

33

How is vitamin A stored in the liver?

As retinol palmitate

34

What is needed to make vitamin D, steroid hormones and bile acids?

Cholesterol

35

Product of HMGcoA reductase?

Mevalonic acid

36

Dietary cholesterol and intrahepatocyte cholesterol reduce activity of what enzyme?

HMGcoA reductase

37

Which vitamin is important for regulation of calcium and phosphorus metabolism?

Vitamin D

38

What is the most abundant form of vitamin D in the circulation?

Vitamin D3

39

What steroid hormones are made from cholesterol?

Corticosteroids, androgens (testis), estrogens (ovary)

40

What converts primary bile salts into secondary bile salts?

Bacteria

41

What mmol/l is considered atherogenic for LDL?

above 4.1

42

What annoying molecules are needed for cholesterol synthesis?

18 mol acetyl coA
16 mol NADPH
36 mol ATP

43

Glycogen storage diseases

Glycogen stored in liver and muscle

44

How are bilirubin, fatty acids and thyroid hormones transported in the body?

Bound to albumin

45

Cholesterol is a precursor for which vitamin?

Vitamin D

46

Role of vitamin D?

Calcium and phosphate metabolism

47

What is the most abundant form of vitamin D in the body?

Vitamin D3