carbohydrates

Question 1

what functional group do carbohydrates contain?

Answer 1

carbonyl and multiple OH groups

Question 2

what are carbohydrates classified by ?

Answer 2

where the carbonyl group is

Question 3

whats a ketone functional group

Answer 3

ketose

Question 4

whats an aldehyde functional group ?

Answer 4

aldose

Question 5

what are the four classification of carbohydrates ?

Answer 5

monosaccharides
disaccharides
oligosaccharides
polysaccharides

Question 6

what is the structure of monosaccharides ?

Answer 6

carbon atoms linked by single bonds. have molecular formulas that are usually multiples of CH2O

Question 7

what is the most common monosaccharide ?

Answer 7

glucose

Question 8

what are monosaccharides classified by ?

Answer 8

the location of the carbonyl group (aldose or ketose)
the number of carbons in the carbon skeleton

Question 9

trioses

Answer 9

3 carbons

Question 10

tetroses

Answer 10

4 carbons

Question 11

pentoses

Answer 11

5 carbons

Question 12

hexoses

Answer 12

6 carbons

Question 13

what is glucose classified as

Answer 13

aldosehexose sugar

Question 14

what is ketose classified as

Answer 14

ketohexose sugar

Question 15

fructose

Answer 15

high content in fruit - twice as sweet as sucrose
used as sweetening agent in processed foods

Question 16

ribose

Answer 16

component of RNA

Question 17

galactose

Answer 17

used to synthesise biomolecules eg glycolipids and glycoproteins

Question 18

what is a membrane carbohydrate bonded to a lipid called?

Answer 18

glycolipids

Question 19

what is a membrane carbohydrate bonded to a protein called ?

Answer 19

glycoproteins

Question 20

how is a disaccharide formed?

Answer 20

when a dehydration reaction joins two monosaccharides

Question 21

what is the name of the bond that joins two monosaccharides together?

Answer 21

glycosidic bond

Question 22

maltose

Answer 22

2 glucose.
C1 of 1 molecules joined through oxygen atom to C4 of other

Question 23

maltose facts

Answer 23

intermediate product of starch hydrolysis.
hydrolysed to glucose by maltase
does not exist freely in nature

Question 24

sucrose

Answer 24

1 glucose 1 fructose
1-2 glycosidic linkage

Question 25

what is the hydrolysis of sucrose to glucose and fructose is catalysed by ?

Answer 25

sucrase

Question 26

lactose

Answer 26

galactose joined to glucose by a 1-4 glycosidic linkage. found in milk

Question 27

what are oligosaccharides?

Answer 27

small polymers of 3-20 monosaccharide residues

Question 28

can oligosaccharides exist on their own?

Answer 28

no, must be attached to a lipid or a protein

Question 29

what do carbohydrates attach to on serine or threonine ?

Answer 29

the side chain O atom residues by O-glycosidic linkages

Question 30

what do carbohydrates attach to on asparagine?

Answer 30

the side chain nitrogen residues by N-glycosidic linkages

Question 31

function of oligosaccharides

Answer 31

protect, cell-cell recognition and binding, lubricate the cell, define the human blood groups

Question 32

what do oligosaccharides protect the cell surface from ?

Answer 32

from mechanical and chemical damage

Question 33

what is an example of cell-cell recognition

Answer 33

Leukocyte (WBC) proteins called lectins recognise particular oligosaccharide side chains on WBC

Question 34

what does lubricating the cell mean ?

Answer 34

when CHO layer adsorb water they give cell slimy surface

Question 35

what does lubricating the cell do?

Answer 35

allows motile cells to squeeze through narrow spaces prevents blood cells from sticking to 1 another or to the walls of blood vessels

Question 36

how do oligosaccharides define the human blood groups ?

Answer 36

A,B & O are structurally related oligosaccharides. all humans synthesise O. A group have a transferase that adds on an extra N-acetylgalactosamine to OAg to form AAg. B group transferase that adds on extra galactose to OAg to form B. people with AB have both transferases.

Question 37

polysaccharides

Answer 37

carbohydrate macromolecules

Question 38

homopolysaccharide

Answer 38

1 monosaccharide type abundant in nature

Question 39

heteropolysaccharide

Answer 39

2 or more types of monosaccharide

Question 40

some storage polysaccharides?

Answer 40

starch , glycogen

Question 41

structural polysaccharide

Answer 41

cellulose

Question 42

starch

Answer 42

a storage polysaccharide of plants, consists entirely of glucose monomers. -2 polysaccharides occur together in starch

Question 43

what are the two polysaccharides in starch

Answer 43

amylose (20-30%) amylopectin (70-80%)

Question 44

amylose

Answer 44

unbranched 1000s of glucose residues long, tight helices

Question 45

amylopectin

Answer 45

branched polymer of glucose subunits prevent helix formation

Question 46

what do plants store surplus starch as?

Answer 46

granules within chloroplasts

Question 47

what enzyme breaks down starch

Answer 47

amylase

Question 48

glycogen

Answer 48

storage polysaccharide of vertebrates mainly liver -muscle cells polymer of linked glucose molecules branch points

Question 49

glucose and fructose are both classified as aldohexose sugars

Answer 49

false