Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bm210 biochemistry > B3 carbohydrates > Flashcards

B3 carbohydrates Flashcards

1
Q

3 carbon monosaccharides and example

A

triose (tri)
glyceraldehyde

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

4 carbon monosaccharides and example

A

tetroses (tetra)
erythrose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

5 carbon monosaccharides and example

A

pentoses (penta)
ribose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

6 carbon monosaccharides and example

A

hexoses (hexa)
glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

7 carbon monosaccharides and example

A

heptoses (hepta)
sedoheptulose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the nutritionally important sugar

A

hexoses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what chemical formula do most sugars conform tp

A

(CH2O)n
where n is between 3 and 7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what chem groups do sugars contain

A

aldehyde groups (-CHO)
or ketone groups (C=O)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what bonds in sugar make it reactive

A

carbon-oxygen double bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does glucose in solution exist mostly as at eqm

A

mostly in ring form
with less than 0.1% of the molecules in the open chain form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what forms by reaction D-glucose of the aldehyde group with an alcohol group

A

hemiacetal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what form is more stable open chain or ring form

A

ring form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the 3 nutritionally important monosaccharides

A

a-D-glucose (pyranose)
galactose (pyranose)
fructose (fructose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how are sugar alcohols formed

A

by the reduction of the aldehyde group of glucose to a hydroxyl group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the energy yield of sugar alcohols

A

roughly half that of glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the energy yield of sugar alcohols

A

roughly half that of glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

example of sugar alcohol and what it is used in

A

sorbitol
used in foods suitable for diabetics as a sweetener
cough syrup
sugar free mints

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what do monosaccharides that are joined to alcohols, amines, and phosphates do

A

signal molecules
facilitate their metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what bond is formed between a monosaccharide and an alcohol or 2 monosaccharides or between a monosaccharide and a protein

A

O-glycosidic bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what bond is formed between a monosaccharide and a nitrogenous base or lysine of a protein

A

N-glycosidic bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does the addition of a phosphoryl group to the monosaccharide do

A

-makes sugars anionic
-traps sugars within the cell
-creates a reactive intermediate of sugar metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the 3 nutritional classes of sugars

A

monosaccharides
disaccharides
oligosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the 2 nutritional classes of polysaccharides

A

starches
non starch polysaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is a disaccharide

A

condensation between two monosaccharides
(O-glycosidic bond)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is an oligosaccharide

A

3-10 monosaccharides
(generally not digested)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is in intrinsic sugar

A

sugars contained within plant cell walls (good ones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is an extrinsic sugar with example

A

sugars that are free in sol
(dental plaque, caries)
exempt lactose being a desirable extrinsic sugar from milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

examples of simple sugars

A

sucrose
fructose
glucose
galactose
maltose
lactose
mannose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

3 most common disaccharide with example and how its made)

A

sucrose
-cane/beet sugar (one glucose one fructose)
lactose
-milk sugar (one glucose one galactose)
maltose (2 glucose)

29
Q

what is the formula of the 3 common disaccharides

A

C12H22O11

30
Q

what is maltose produced in

A

produced in germinating cereals (barley)
in the brewing process
“malting” barley is through maltose producing amylases

31
Q

what does mashing permit in geminating cereals

A

permits the amylases to convert the cereals starches into maltose

32
Q

what does yeast ferment maltose to produce

A

ethanol and carbon dioxide

33
Q

sucrose

A

cane or beet sugar
glucosyl-fructose

34
Q

maltose

A

originally isolated from malt
glucosyl-glucose

35
Q

isomaltose

A

isoform of maltose linked 1-6

36
Q

lactose

A

sugar of milk
galactosyl-glucose

37
Q

trehalose

A

especially in mushrooms
glucosyl-glucose

38
Q

what type of bond does maltose have

A

a-1,4-glycosidic bond

39
Q

what is starch

A

large mol with variable number of glucose units
storage carb of plants (not osmotically active)

40
Q

what are the two forms of starch

A

amylose
amlylopectin

41
Q

what is amylose

A

chain of glucose mols (a-1,4)

42
Q

what is amylopectin

A

chain of glucose mols (a-1,4) every 30th glucose branch to other glucose residues (a-1,6)

43
Q

what is glycogen

A

storage carb of mammalian muscle and liver
similar to amylopectin but branch every 10th glucose

44
Q

what are non starch polysaccharides and examples

A

not digested by human enzymes
cellulose (glucose linked b-1,4)
chitin
pectin

45
Q

why is uncooked starch resistant to digestion and what does cooking starch do

A

because its present as small insoluble granules
cooking swells the granules

46
Q

what is a lactose intolerance

A

the inability to metabolise milk sugar lactose

47
Q

what is the % of the level at birth of lactase activity

A

decrease to 5-10%

48
Q

lactose is used as an energy source for what, where

A

microorganisms in the colon

49
Q

what does fermentation of lactose produce

A

methane and hydrogen gas

50
Q

why is flatulence and diarrhoea a result of lactose intolerance

A

as lactate is osmotically active and draws water into the intestine

51
Q

why is glycogen not as energy rich as fatty acids

A

less reduced

52
Q

what maintains BGL

A

controlled release of glucose from glycogen

53
Q

where is glycogen mainly stored

A

liver and skeletal muscle

54
Q

in the liver hapatocytes, glycogen can compose what % of the fresh weight

A

8-10%
(100-120g in adult)

55
Q

what % of muscle mass can be glycogen

A

1-2%

56
Q

why does the uterus store glycogen during pregnancy

A

to nourish the embryo

57
Q

polysaccharides have a reducing and a non reducing end, what does this mean

A

that they have directionality

58
Q

what is an acetal and what does it prevent

A

a mol with 2 single bonded oxygens attached to the same carbon atom
prevents opening of the chain to the aldehyde form and renders this end non reducing

59
Q

does glycogen have a reducing end

A

no

60
Q

what is the reducing end glucose residue bound to

A

covalently bound to a glycogenin as a beta linkage to a surface tyrosine residue

61
Q

what is glycogenin and where does it sit

A

a glycosyltransferase and sits as a dimer in the core of glycogen

62
Q

what do the glycogen granules contain

A

both glycogen and the enzymes of glycogen synthesis (glycogenesis) and degradation (glycogenolysis)

63
Q

where are the enzymes for glycogenesis and glycogenolysis
and where do they act

A

nested between the outer branches of the glycogen mols and act on the non reducing ends

64
Q

what facilitates glycogens rapid synthesis and catabolism

A

the many non reducing ends

65
Q

what proteins are frequently glycosylated

A

cell surface proteins
secreted proteins

66
Q

where does O-glycosylation occur

A

at serine or threonine in the golgi

67
Q

where does N-glycosylation occur

A

at asparagine in the ER followed by modification in the golgi

68
Q

what is the motif for N-glycosylation

A

is Asn-X-Thr/Ser (X=any aa except proline)

69
Q

what is the reversible intracellular glycosylation to sense nutrient abundance

A

O-linked GlcNAc

70
Q

what are proteoglycans and what is the dominant component

A

proteins modified with glycosaminoglycans (structural components and lubricants)
carbohydrate (95%)

71
Q

what are mucins and what is it the key component of

A

attachment to protein via N-actylgalactosamine
key component of music (protective barrier)

bm210 biochemistry (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions