MCP

Question 1

Carbohydrates

Answer 1

• chemical formulas = (CH2O)n, where n >/= 3
• basic carbohydrate unit = monosaccharide
• monosaccharides may be covalently linked together to form oligosaccharides and polysaccharides

Question 2

Monosaccharides

Answer 2

-classified by the number of carbons such as pentose for 5 carbons and hexoses for 6 carbons

Question 3

what are the smallest monosaccharides? and how many carbons do they have?

Answer 3

Trioses, 3 carbons

Question 4

What are monosaccharides classifications based on? What are the two types?

Answer 4

• based on chemical nature of the carbonyl group
• aldose if carbonyl is an aldehyde
• ketose if carbonyl is a ketone

Question 5

What are the most common aldoses?

Answer 5

• glyceraldehyde (triose)
• ribose (pentose)
• glucose, mannose and galactose (hexoses)

Question 6

what are the most common ketoses?

Answer 6

• dihydoxyacetone (triose)
• ribulose (pentose)
• fructose (hexoses)

Question 7

What form are monosaccharides most often found in ?

Answer 7

CYCLIC

Question 8

What is the anomeric carbon?

Answer 8

anomeric carbon is the carbon -which was the former carbonyl carbon which when forming cyclic rings reacts with one of the -OH groups to form a hemiacetal or hemiketal

• C1 in aldoses
• C2 in Ketoses

Question 9

What is a reducing sugar?

Answer 9

A reducing sugar is an anomeric carbon that’s oxygen does not have anything else bound to it -with anomeric carbon considered the reducing end

Question 10

What type of bond links monosaccharides ?

Answer 10

glycosidic bonds

Question 11

Define Disaccharide

Answer 11

two sugar residues covalently linked via a glycosidic bond

Question 12

Define Oligosaccharide

Answer 12

short typically 2-15 sugars linear or branched chain of sugars covalently bound to one another via glycosidic linkages

Question 13

Define polysaccharide

Answer 13

long linear or branched polymer of sugar covalently bound or linked to one another via glycosidic linkages (may consist of hundreds of sugars)

Question 14

Where are carbohydrates principally digested?

Answer 14

the mouth and small intestines

Question 15

amylose

Answer 15

found in starch linear polysaccharide consisting of 100s to 1,000,000 of glucose residues in alpha-1,4 linkage

Question 16

amylopectin

Answer 16

found in starch- branched polysaccharide consisting of 100s to 1,000,000s of glucose residues in alpha -1,4 linkage with alpha-1,6 branches

Question 17

lactose

Answer 17

dissacharide consisting of galactose and glucose in beta-1,4 linkage; found in dairy and milk products

Question 18

sucrose

Answer 18

(table sugar) -disaccharide consisting of glucose and fructose in alpha-1,2 linkage; this is a non-reducing sugar because of the -OH’s of the two anomeric carbons are not free

Question 19

glycogen

Answer 19

branched polysaccharide consisting of hundreds to millions of glucose residues in alpha-1,4 linkage with alpha-1,6 branches; same basic structure as amylopectin, but more highly branched; storage form of glucose found in most cells greatest in liver and skeletal muscle

Question 20

Cellulose

Answer 20

(major component of dietary fiber) -linear polysaccharide consisting of hundreds to millions of glucose residues in Beta-1,4 linkage; cannot be digested by humans because we don’t have the enzyme that will cleave the glucose to glucose beta-1,4 linkage

Question 21

Define glycosidases

Answer 21

a large group of enzymes that cleave a wide array of glycosidic linkages

Question 22

endogylcosidases

Answer 22

cleave internal glycosidic bonds in sugar plymers

Question 23

exoglycosidases

Answer 23

cleave terminal glycosidic bonds in sugar polymers

Question 24

disaccahridases

Answer 24

cleave glycosidic bonds in disaccharides

Question 25

What factors determine the specific glycosidase used?

Answer 25

1. structure of the glycosidic linkage 2. specific sugars on either side of the linkage 3. position of the glycosidic linkage within the polymer (i.e. terminal vs. internal)

Question 26

Alpha amylase

Answer 26

endoglucosidase that hydrolyzes random internal alpha-1,4 bonds between glucose residues in starch (both amylopectin and amylose)

Question 27

Salivary alpha amylase

Answer 27

produced in the salivary glands in the mouth-cleaves starch polymers into smaller polysaccharides. It is inactivated in the stomach (bc of acidic pH)

Question 28

Pancreatic alpha amylase

Answer 28

produced by the pancreas and secreted into the duodenum- it continues hydrolyzing the starch digestion products to produce maltose, maltotriose and longer linear oligosaccharides, alpha dextrins and isomaltose

Question 29

Dextrin

Answer 29

oligosaccharide which has at least one alpha-1,6 linkage by definition

Question 30

Glucoamylase

Answer 30

an exoglucosidase that cleaves a terminal alpha-1,4 bond between glucose beginning in the non-reducing end; substrates include maltose, maltotriose, alpha dextrin, amylose, and amylopectin; produces glucose and isomaltose

Question 31

maltase

Answer 31

cleaves the alpha-1,4 bond in maltose and maltotirose to produce glucose and maltose

Question 32

isomaltase

Answer 32

cleaves the alpha-1,6 bond in the isomaltose and alpha dextrins to produce glucose and glucose polymers

Question 33

sucrase

Answer 33

cleaves the alpha-1,2 bond in sucrose to produce glucose and fructose

Question 34

lactase

Answer 34

cleaves the beta-1,4 bond in lactose to produce galactose and glucose

Question 35

Lactose Intolerance

Answer 35

found in 75% of world's population- because evolutionary new trait to be able to digest milk beyond infancy and childhood - must cause symptoms to be considered lactose intolerant

Question 36

Tay Sachs Disease

Answer 36

defect in enzyme = B- hexosaminidase | accumulated substrate = gangliosides G M2

Question 37

Gaucher disease

Answer 37

enzyme = Beta glucossidases | accumulation of glucocerebrosides

Question 38

Metachromatic Leukodystrophy

Answer 38

enzyme = arylsulfatase | accumulation of sulfatides

Question 39

Krabbe disease (Globoid cell leukodystrophy)

Answer 39

enzyme= Beta galactosidases | accumulation of galactocerebrosides

Question 40

Gangliosidosis

Answer 40

enzyme = beta galactosidases | accumulation of gangliosides

Question 41

Sandhoff disease

Answer 41

enzyme beta hexosaminidase | accumulation of globosides

Question 42

Farby disease

Answer 42

enzyme - alpha galactosidase accumulation of globosides X LINKED

Question 43

Nieman-Pick Disease (A + B)

Answer 43

Enzyme= sphingomyelinase | accumulation of sphingomyelin

Question 44

Farber disease

Answer 44

enzyme = ceraminidase | accumulation of ceramide