carbohydrates Flashcards

1
Q

where are carbohydrates produced

A

by photosynthesis

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

what are carbs oxidised to produce

A

CO2 and H2O and energy

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

what is a monosaccharide

A

the simplest carbohydrates, no hydrolysis occurs
3 to 6 carbon atoms
a carbonyl group
several hydroxide groups

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

what is disaccharide

A

two monosaccharide units

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

what is a polysaccharide

A

many monosaccharide units

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

what is an olagasaccharide

A

3 to 10 monosaccharide units

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

what is an aldose

A

monosaccharides with an aldehyde group, also have many hydroxyl group
(triose, tetrose, pentose, hexose)

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

what is a ketose

A

monosaccharides with a ketone group with many hydroxyl group

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

fischer projection

A

used to represent carbohydrates
most oxidised group goes at the top
chiral carbons at in the middle of the structure

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

whats the difference between a D-glyceraldehyde and an L- glyceraldehyde

A

L- hydroxyl group on the left of the chiral carbon
D- hydroxyl group on the right of the chiral carbon

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

what determines the L or D status of a glyceraldehyde

A

the hydroxyl group farthest away from the chiral carbon

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

what is an epimer

A

structures that differ at one chiral centre

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

galactosemia

A

when there is a lack of enzymes reuired for galactose metabolism, results in an accumulation of galactose intermediates which has toxic effects in the liver, brain, kidneys and eyes

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

are cyclic or linear monosaccarides more stable

A

cyclic

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

when are cyclic monosaccharides produced

A

when the hydroxyl group of C-5 reacts with the aldehyde group or ketone group

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

whats the differnce between an alpha-D-glucose and a beta-D-glucose

A

alpha-below the ring
beta- above the ring

17
Q

what happens when alpha-D-glucose or beta-D-glucose is in solution

A

clyclic structures open and close

18
Q

how to test for sugars (ex. glucose) in the blood

A

use fehlings solution to convert a glucose into a gluconate by reducing inorganic ions such as copper

19
Q

what is a reducing sugar

A

a sugar that will reduce inorganic ions such as Cu++
(ex. aldoses and ketoses)

20
Q

what is a glucose oxidase test

A

‘dip stick test’ quicker way to test for glucose in the urine

21
Q

whats the lifetime of red blood cells

22
Q

what is lactose made up from

A

disaccharide between glucose and galactose
found in milk and milk products

23
Q

what is a lactose intolerance

A

lack of lactase enzyme in small intestine which means lactose can pass onto the colon, bacteria start to ferment lactose causing stomach cramps and bloating

24
Q

what class of carbohydrate is glycogen

A

highly branched polysaccharide composed of multiple glucose units

25
what does an alpha bond look like in glycogen
below the ring
26
what is sucrose made up from
glucose and fructose
27
what is maltose made up from
2 units of glucose
28
what is starch
plant form of carbohydrate ingested by humans
29
what is amylose
unbranched starch comprised of glucose units hydrolysed by alpha-amylase secreted by salivary glands in the pancreas
30
amylopectin
branched form of starch hydrolysed by alpha-amylase secreted by salivary glands in the pancreas
31
ratio of amylose and amylopectin in starch
20% amylose 80% amylopectin
32
cellulose
storage in plants contains a beta-1,4 linkage (above the ring) mammals lack cellulases
33