Brainscape's Knowledge GenomeTM

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


See full index

Bio - Unit 1 Biological Molecules - Monomers and Polymers > Carbohydrates > Flashcards

Carbohydrates Flashcards

You may prefer our related Brainscape-certified flashcards:
Organic Chemistry 101 flashcards Biology 101 flashcards
1
Q

What are monomers?

A

Monomers are the smaller units from which larger molecules (polymers) are made up of

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

What are polymers?

A

Larger molecules made up of smaller repeating units (monomers)

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

What are monosaccharides?

A

Monomers of Carbohydrates

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

What are the 3 monosaccharides?

A

Glucose
Galactose
Fructose

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

What is a disaccharide?

A

Two monosaccharides chemically joined together by a glycosidic bond formed in a condensation reaction.

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

What are the 3 disaccharides?

A

Maltose
Lactose
Sucrose

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

Which 2 monosaccharides join together to make Maltose + water

A

Glucose + Glucose

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

Which two monosaccharides join together to make Lactose + water

A

Glucose + Galactose
(hint-galactose has the word lactose in it)

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

Which two monosaccharides join together to make Sucrose + water

A

Glucose + Fructose

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

General Formula for Monosaccharides

A

(CH2O)n
n = 1-7

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

What is an isomer?

A

Molecules with the same molecular formula but different structure

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

What are the 2 isomers of glucose

A

Alpha Glucose & Beta Glucose

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

Alpha Glucose

A

C6H12O6
Hexose Sugar (hexagon)

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

Which way is the Hydroxyl group (OH) on alpha glucose

A

ABBA (Alpha below, Beta above)
Hydroxyl (OH) group on the bottom of Carbon 1 & 4
Hydrogen (H) on top of Carbon 1 & 4

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

Which way is the Hydroxyl (OH) group on Beta glucose?

A

ABBA (Alpha below, Beta above)
Hydroxyl group is on top of Carbon 1 on beta glucose (Hydrogen on the bottom)
Hydroxyl group is on the bottom of Carbon 4 (Hydrogen on top)

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

What is a condensation reaction?

A

A glycosidic bond forms - alpha (1-4) glycosidic bond
A water molecule is released
Joins 2 molecules together by removing water
Normally catalysed by an enzyme
Polymer molecules made from monomers
Bond formed, H2O removed

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

What happens when the glycosidic bond forms?

A

A water molecule is released
via a condensation reaction

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

What is a hydrolysis reaction?

A

A water molecule is used up
A glycosidic bond breaks
Polymers broken down into monomers
Breaks a chemical bond between 2 molecules and involves the removal of a water molecule
Normally catalysed by an enzyme
Bond broken , H2O added

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

Anabolic and Catabolic

A

Anabolic - Making larger molecules from simpler ones
Catabolic - Making smaller molecules from larger ones

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

Where does the glycosidic bond form?

A

Between Carbon 1 and Carbon 4
OH + H
H2O so water is removed

21
Q

What is the general formula for disaccharides?

A

C6H12O6+C6H12O6=C12H22O11 + H2O
General Formula = C12H22O11

22
Q

Structure of Glucose (a)

A

Oxygen top right corner
Carbon 1 - H on top,OH on the bottom
Carbon 2 , Carbon 3
Carbon 4 - H on top,OH on bottom
Carbon 5 Top left corner
Carbon 6 - CH2OH on top of Carbon 5

23
Q

Structure of Galactose

A

Same as Glucose except :
Hydroxyl group (OH) on carbon 4 is the opposite
OH on top, H on the bottom

24
Q

Structure of Fructose

A

Pentagon
Oxygen on the top point
Carbon order is anti clockwise
Carbon 2 - Top left
Carbon 2 has HO on the bottom and H2COH on top (carbon 1)
Carbon 1 - On top of carbon 2 H2COH
Carbon 3 - Bottom Left
Carbon 4 - Bottom Right
Carbon 5 - Top Right
Carbon 5 has H on top and CH2OH on the bottom (carbon 6)
Carbon 6 - Bottom of Carbon 5 CH2OH

25
Q

What is the bond formed in maltose?

A

alpha (1-4) glycosidic bond
always have water as a product

26
Q

What is the bond formed in Lactose

A

alpha (1-4) glycosidic bond
always have water as a product

27
Q

What is the bond formed in Sucrose

A

alpha (1-2) glycosidic bond
always have water as a product

28
Q

Hydrolysis enzymes for Maltose, Lactose and Sucrose

A

Maltose —> Maltase
Lactose —> Lactase
Sucrose —> Sucrase

29
Q

What are the 3 tests for Carbohydrates

A

1) Benedict’s test for reducing sugars (glucose, galactose, maltose, fructose)
2) Benedict’s test for non reducing sugars (sucrose)
3) Iodine test for starch

30
Q

What is the Reducing Sugars test

A

Reduction is a chemical reaction involving the gain of electrons or hydrogen
A reducing sugar is a sugar that can donate electrons to another chemical (reduce it) in this case benedict’s reagent

31
Q

What is Benedict’s solution?

A

An alkaline solution of Copper (II) sulfate
When a reducing sugar is heated in boiling water with benedict’s reagent it forms an insoluble red precipitate of Copper (I) oxide
The copper (II) sulfate gains an electron and becomes copper (I) sulfate
The sugar has been oxidised (loss of electrons)

32
Q

Benedict’s test for reducing sugars steps

A

1) Add 2cm3 of Benedict’s solution and 2cm3 of the test solution in a test tube
2) Heat in a boiling water bath (95°c)
3)Boil mixture for 5 minutes and observe any colour change
Positive result = Colour change from light blue to brick red ppt
- Reducing sugar is present
Negative result (Non reducing sugar-Sucrose) = No colour change to test solution
- Solution stays light blue

Weaker solution of reducing sugar may be : green, yellow or orange ppt when heated with benedict’s reagent

33
Q

Benedict’s test for Non-Reducing Sugars (Sucrose)

A

No change in first test for reducing sugar = boil a fresh sample with dilute HCL for a few minutes to hydrolyse the glycosidic bonds to break down into its monosaccharides
2) Neutralise the solution by adding small amounts of solid sodium hydrogen carbonate (NaHCO3)
3) Then test as before for reducing sugars using benedict’s reagent
4) Sucrose has now been hydrolysed into its monosaccharides glucose and fructose which are reducing sugars so it will react and give a positive result

1) Hydrolyse Glycosidic bonds
2) Neutralise solution
3) Test as normal

34
Q

What are Polysaccharides?

A

Long chains of repeating monosaccharides chemically joined together by glycosidic bonds

35
Q

Classification of Carbohydrates

A

Sugars - Monosaccharides & Disaccharides
Polysaccharides- Storage & Structure

36
Q

Which polysaccharides are used for storage?

A

Starch
Glycogen

37
Q

Which polysaccharide is used for structure?

A

Cellulose

38
Q

What are the main features of polysaccharides?

A

Large & Insoluble
Non reducing - give negative results in benedict’s test
Joined by Glycosidic bonds
Polymers
Used for storage or structure

39
Q

What are the main features of polysaccharides?

A

Large & Insoluble
Non reducing - give negative results in benedict’s test
Joined by Glycosidic bonds
Polymers
Used for storage or structure

40
Q

Starch (storage)

A

-Long, branched chains of alpha glucose
-Stored in starch grains in the cytoplasm plant cells
- energy store in plants (chloroplasts)
- Compact - lots can be stored in small spaces
- Some branching
- Helical shape makes it compact
- Amylase enzyme breaks down starch
- Branched structure allows glucose molecules to be easily released
- Glucose molecules released for respiration
- Large molecule so it can’t cross the cell membrane
a((1-6) glycosidic bond

41
Q

Hydrolysis of Starch

A

-Hydrolysed by the enzyme amylase to produce the disaccharide maltose
-Starch + Water —> Maltose
Polysaccharide —> Disaccharide

42
Q

Amylose and Amylopectin

A

Polymers of Alpha Glucose
Amylose - alpha(1-4) glycosidic bond
Amylopectin - alpha(1-4) and (1-6) bond
(1-6) bind forms where the branch starts

43
Q

Glycogen (Storage)

A

Energy store in animals
Alpha glucose monomers
Insoluble & osmotically inactive
Very branched
Rapid hydrogenation
Stored as small granules, particularly in muscles and liver
a(1-6) glycosidic bonds

44
Q

Why is glycogen stored in animals?

A

Animals are active
The glycogen needs to hydrolyse wuicky to release more glucose for respiration which provided energy

45
Q

Cellulose (Structure)

A

Chains of BETA glucose monomers
Strong and Rigid
Prevents plant cells bursting
Allows cells to be turgid - supports leaves
Maximum surface area for photosynthesis
Permeable to water

46
Q

Cellulose (structure) pt2

A

Straight chain polymer
Beta(1-4) linkages
Contrast a(1-4) glycosidic bonds un started and glycogen
No coiling or branching instead an extended and stiff rod-like shape

47
Q

Beta - Glucose unit rotation

A

Beta Glucose units are rotated by 180° relative to the neighbouring unit
1 unit is flipped upside down so a bond can be formed horizontally not diagonally between the OH group

48
Q

Cellulose

A

Strands of cellulose have hydrogen bonds between OH groups which increases stability
Hydrogen bonds form cross links between chains which provides strength to the cell walls
Weak hydrogen bonds provide strength in numbers
Cellulose gives the plant cell rigidity because the cellulose cell wall is inelastic and has a high tensile strength to prevent the plant cells from bursting

Bio - Unit 1 Biological Molecules - Monomers and Polymers (3 decks)

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