Carbs 1 and 2

Question 0

what is the OH group’s linkage if it is below the plane of the sugar?

Answer 0

alpha

Question 1

Do our bodies utilize D or L sugars?

Answer 1

D

Question 2

what is the OH group’s linkage if it is above the plane of the sugar?

Answer 2

beta

Question 3

what type of bonds link sugars?

Answer 3

glycosidic bond

Question 4

what sort of group is found on a reducing sugar?

Answer 4

reactive carbonyl (Hemiacetals)
which can reduce metals hence the name
swaps H+ on the carbonyl group with an O

Question 5

Anomeric carbon

Answer 5

reducing carbon on a sugar

Question 6

Which end of a oligo or poly - saccharide has the anomeric carbon?

Answer 6

reducing end

Question 7

A patient is found to be unable to absorb disaccharides, what could be the issue?

Answer 7

An enzyme in the gut called disaccharidases which are tethered to cells in the lumen and breakdown disaccharides into monosaccharides. this is could be the culprit because we can only absorb monosaccharides

Question 8

what cleaves an alpha 1,6 bond?

Answer 8

Isomaltase

Question 9

What cleaves an alpha 1,1 bond?

Answer 9

Trehalose

Question 10

what breaks an beta 1,4 bond?

Answer 10

Lactase

Lactose = galactose and glucose

Question 11

what pathways does G6P participate in?

Answer 11

Glycolysis
Pentose phosphate pathway
glycogen synthesis

Question 12

what type of link bonds branches to glycogen molecules?

Answer 12

alpha 1,6

Question 13

every polymer of glycogen is attached to _____

Answer 13

glycogenin

which is a protein

Question 14

what enzyme is responsible for the conversion of G6P to G1P?

Answer 14

phosphoglucomutase

Question 15

what are the building blocks of glycogen?

Answer 15

UDP-Glucose

Question 17

What starts the seeding process for glycogen?

Answer 17

When glycogenin glycosylates itself by attaching the glucosyl residue of UDP-glucose to the hydroxyl chain of a Ser residue in the protein

Question 18

What link connects branches to the core glycogen molecule?

Answer 18

alpha 1,6

Question 19

glycogen degradation proceeds through a _______ rxn

Answer 19

phosphorolysis

use of phosphate to break the bond

Question 20

Why is an ATP not required to make G6P for glycolysis ?

Answer 20

G1P and G6P are energetically equivalent

Question 21

what is the activity of glycogen phosphorylase?

Answer 21

will cut down the glycogen chains to “limit dextrins”

Question 22

Glycogen phosphorylase and glycogen synthase are reciprocally regulated.by…

Answer 22

phosphorylation with ATP

Question 23

When glycogen phosphorylase B is phosphorylated then it is (active/inactive)

Answer 23

active

Question 24

Insulin secretion in response to an increase in blood sugar levels induces …

Answer 24

more GLUT4 receptors to come to the cell surface to increase uptake of glucose

Question 25

Glucagon signals to the liver result in ...

Answer 25

the conversion of glycogen phosphorylase B to glycogen phosphorylase A and the inhibition of glycogen synthase

Question 26

Fructose metabolism occurs in ...

Answer 26

the liver

Question 27

What does the Pentose phosphate pathway generate?

Answer 27

5 carbon sugars and NADPH

Question 28

What intermediate links the Fructose metabolism pathway to Glycolysis?

Answer 28

DHAP - dihydroxyacetone phosphate

Question 29

Name the three enzymes involved in Fructose metabolism

Answer 29

Fructokinase Aldolase B Triose Kinase

Question 30

Hereditary Fructose intolerance is characterized by ....

Answer 30

insufficient Aldolase B activity causing pts to accumulate very large stores of F1P symptoms: Jaundice, vomiting and convulsions

Question 31

What does the Pentose phosphate pathway produce?

Answer 31

NADPH | Ribose 5-phosphate

Question 32

What does the first (oxidative phase)stage of the PPP generate ?

Answer 32

2 moles of NADPH per 1 mole of G6P

Question 33

What does the second (non oxidative phase)stage of the PPP generate ?

Answer 33

ribose 5 phosphate | converts unused intermediates to fructose 6-P and glyceraldehyde 3-P

Question 34

What pathway do RBCs rely on to avoid oxidative damage?

Answer 34

HMP shunt

Question 35

What can not be oxidized by the electron transport chain?

Answer 35

NADPH

Question 36

What molecules does UDP glucose serve as a percursor for?

Answer 36

glycosides lactose glycolipids glycoproteins

Question 37

What is the ocular consequence and mechanisms of elevated sugar in diabetes?

Answer 37

elevated glucose leads to generation of fructose in the lens of the eye. Excess will be converted to sorbitol at a faster rate then it can be cleared. Leads to increase in osmotic pressure

Question 38

What are the functions of Glucuronides?

Answer 38

to aid in excertion of bilirubin and drugs overall it supplys negatively charged group to couple with OH on the target molecule More charges = increased solubility

Question 39

describe synthesis of lactose

Answer 39

Galactose is produced from conversion of UDP-glucose to UDP-galactose by epimerase then glucose and galactose are linked by an alpha bond

Question 40

What residues on proteins are short carbohydrates attached?

Answer 40

serine threonine asparagine

Question 41

What are the general features of glycoproteins?

Answer 41

highly branched | no repeating disaccharide units

Question 42

what are the functions of glycoproteins?

Answer 42

most proteins in the blood - clotting enzyme, antibodies, hormones structural components of ECM - collagen Mucus secretions

Question 43

What is the primary component of the glycolipid, sphingosine?

Answer 43

ceramide with carbohydrate pieces

Question 44

What is a function of glycolipids?

Answer 44

cell recognition | example: ABO blood groups

Question 45

Name the enzymes that metabolize ETOH

Answer 45

liver alcohol dehydrogenase Microsomal ethanol oxidizing system (MEOS)

Question 46

What is the side effect of the metabolism of the small alcohol, ETOH?

Answer 46

ADHs have preferences for different chain lengths of alcohols at high concentrations, ETOH will be non specifically metabolized leading to large increase in amount of Acetaldehyde bi product which is toxic leads to nausea and vomiting

Question 47

Where is the liver cell is the majority of ETOH metabolized?

Answer 47

Mitochondrial ALDH2 | an allelic variance of ALDH2 which has very low affinity for substrate confers resistance to alcoholism

Question 48

In the liver, acetyl CoA will be used in ....

Answer 48

cholesterol and fatty acid synthesis

Question 49

What is MEOS composed of?

Answer 49

Cytochrome P 450 reductase and cytochrome P 450 | oxidizes ETOH to acetaldehyde

Question 50

What enzyme shows the most activity toward ETOH?

Answer 50

CYP2E1

Question 51

Chronic ETOH consumption leads to ...

Answer 51

increasing the NADH/NAD+ ratio resulting in changes to fatty acid metabolism, ketoacidosis, lactic acidosis, hyperuricemia and hypoglycemia

Question 52

What are the consequences of excessive drinking, with respect to fatty acid metabolism?

Answer 52

inhibition of oxidation of fatty acids leading to the accumulation increases in the amount of triacylglycerols which are incorporated to VLDLs which build up in liver and enter the blood

Question 53

What conditions are the result of excess ETOH? Think about what happens metabolically

Answer 53

Hyperlipidemia | fatty liver

Question 54

What is the mechanism of Alcohol induced ketoacidosis?

Answer 54

High NADH leads to reversal of Acetyl CoA to the TCA cycle instead Acetyl CoA is used to generate ketone bodies build up in the blood is toxic

Question 55

What is the consequence of Lactic acidosis?

Answer 55

the altered NADH/NAD+ ratio will shift the reaction of lactate dehydrogenase towards lactate High lactate will lead to decreased excretion of uric acid => Gout Lactate also inhibits gluconeogenesis so fasting blood sugar levels drop

Question 56

pt with mutation in CYP2E1 rendering protein non functional, what do expect to happen when pt consumes large amount of alcohol?

Answer 56

majority of ingested ethanol would get converted into acetaldehyde via ADH