P2. Carbohydrates Flashcards
(93 cards)
1
Q
provides energy
A
Carbohydrate oxidation
2
Q
Carbohydrate storage, in the form of ____, provides a short-term energy reserve.
A
glycogen
- human and animal energy storage
- can be found in the liver
3
Q
- supply carbon atoms for the synthesis of other biochemical substances (proteins, lipids, and nucleic acids)
- form part of the structural framework of DNA and RNA molecules.
A
Carbohydrates
4
Q
Carbohydrates linked to lipids are structural components of?
A
cell membranes
5
Q
Carbohydrates linked to proteins function in a variety of ____ recognition processes.
A
cell–cell and cell–molecule
6
Q
- a compound that yields polyhydroxy aldehydes or polyhydroxy ketones upon hydrolysis.
A
carbohydrates
7
Q
is a polyhydroxy aldehyde
A
carbohydrate glucose
8
Q
is a polyhydroxy ketone.
A
carbohydrate fructose
9
Q
Classifications of Carbohydrates:
A
monosaccharides
disaccharides
oligosaccharides
polysaccharides
10
Q
- are classified as aldose or ketose on the basis of the type of carbonyl present.
A
Monosaccharides
11
Q
glycosides formed from the linkage of two monosaccharides.
A
Disaccharides
Disaccharides is the most important Oligosaccharides.
12
Q
carbohydrates that
contain three to ten monosaccharide units.
A
Oligosaccharides
13
Q
- are polymers.
- are monomers.
A
- polysaccharides
- monosaccharides
14
Q
- handedness in molecules
- objects & mirror images
A
Chirality
15
Q
The 2 existant forms of monosaccharides:
A
- left handed form
- right handed form
16
Q
- images that coincide at all points when the images are laid upon each other.
- same reflection
- an object and it’s mirror image are identical and can’t be distinguished
A
Superimposable mirror images
17
Q
- are images where not all points coincide when the images are laid upon each other.
- an object and it’s mirror image are different and can be distinguished
A
Nonsuperimposable mirror images
18
Q
- an atom in a molecule that has four different groups bonded to it in a tetrahedral orientation.
an atom that has four different groups bonded to it in such a manner that it has a nonsuperimposable mirror image.
A
chiral center
19
Q
- molecule that contains a chiral center and it’s nonsuperimposable w/ features of handedness.
- molecule that doesn’t contain a chiral center and it’s superimposable w/o features of handedness.
A
- chiral
- achiral
20
Q
molecule whose mirror images are not superimposable (meaning NONSUPERIMPOSABLE).
A
chiral molecule
21
Q
it is the left & right handed form of chiral molecules
A
STEREOISOMERISM/ ISOMERS
22
Q
**
- connected in the same way but are arranged differently in space.
- same formula but different in structures/space.
A
Stereoisomerism
23
Q
Two types of Stereoisomerism:
A
- enantiomers
- diastereomers
24
Q
- have structures that are nonsuperimposable mirror images of each other
A
Enantiomers
25
- have structures that are **not nonsuperimposable mirror images of each other**
Diastereomers
26
PROPERTIES OF ENANTIOMERS:
1. constitutional isomers
2. diastereomers
27
-differ in most chemical and physical properties.
## Footnote
have different boiling points and melting points.
Constitutional isomers
28
also **differ in most chemical and physical properties**. They also have different boiling points and freezingpoints
Diastereomers
29
nearly all the properties of a pair of enantiomers are the same.
Two differences:
1. Their interaction with **plane polarized light**
2. Their interaction with **other chiral substances**
30
Enantiomers are ____: Compounds that rotate ____.
1. optically active
2. plane polarized light
31
Two types of Enantiomers Plane Polarized Light:
1. dextrorotary
2. levorotary
32
- D-type
- present in our body
- RIGHT hydroxyl group
- towards the right light movement/ clockwise
- positive sign
dextrorotary
33
- L-type
- LEFT hydroxyl group
- towards the left light movement/ counterclockwise
- negative sign
## Footnote
L-sucrose and L-fructose are present in animals
levorotary
34
In D and L you need to look at the structure + and - are determined by using a ____.
polarimeter
35
is a **two-dimensional structural notation** for showing the **spatial arrangement of groups about chiral centers** in
molecules.
Fischer projection formula
36
usually the Chiral Center represents what element?
Carbon
37
In a Fischer projection formula a ____ is **represented as the intersection of vertical and horizontal lines**
Chiral Center (Carbon)
38
used to **designate the handedness of glyceraldehyde enantiomers.**
## Footnote
can be extended to other monosaccharides with more than one chiral center.
D and L system
39
1. is numbered **starting at the carbonyl group end** of the molecule
2. is used to **determine D or L configuration.**
1. carbon chain
2. highest-numbered chiral center
40
- are often **classified** by both their **number of carbon atoms and their functional group.**
- cannot be further hydrolyse to smaller compounds
Monosaccharides
## Footnote
- PENTOSE & HEXOSE are the most important monosaccharides base on human standards.
41
**six-carbon monosaccharide** with an **aldehyde functional** group is an
aldohexose
42
five-carbon monosaccharide with a ketone functional group is a
ketopentose
43
- the **most abundant in nature**
- the **most important from a human nutritional standpoint**.
D-glucose/ aldohexose
44
- biochemically the **most important ketohexose**
- also known as **levulose and fruit sugar.**
D-Fructose/ ketohexose
45
1. Milk sugar
2. Synthesize in human
3. Used to differentiate between blood types
4. Six membered cyclic form
D-Galactose/ Aldohexose
46
1. Part of RNA
2. Part ofATP
3. Part of DNA
4. Five membered cyclic form
D-Ribose/ Aldopentose
47
2 forms of D-glucose:
alpha-form
beta-form
48
C1: -OH
C5: CH2OH
(they are on opposite sides)
Alpha-form
49
C1: -OH
C5: CH2OH
(they are on the same sides)
Beta-form
50
a two-dimensional structural notation that **specifies the three-dimensional structure of a cyclic form of a monosaccharides.**
HAWORTH PROJECTION FORMULAS
51
determined by the **position of the —OH group on C1 relative to the CH2OH group** that *determines D or L series.*
## Footnote
1. both of these groups point in the **same direction**
2. the two groups point in **opposite directions**
Alpha or Beta configuration
## Footnote
1. Beta configuration
2. Alpha configuration
52
The **specific identity of a monosaccharide** is determined by the **positioning of** the other ____ in the ____.
1. —OH groups
2. Haworth projection formula
53
1. any -OH group to the **right** of the FISCHER PROJECTION FORMULA points ____ to the HAWORTH PROJECTION FORMULA.
2. any -OH group to the **left** of the FISCHER PROJECTION FORMULA points ____ to the HAWORTH PROJECTION FORMULA.
1. DOWN
2. UP
54
Five important reactions
monosaccharides:
1. OXIDATION to acidic sugars
2. REDUCTION to sugar alcohols
3. Glycoside formation
4. Phosphate ester formation
5. Amino Sugar formation
55
- redox chemistry of monosaccharides is **closely linked to the alcohol and aldehyde functional groups presen**t in them.
- can **yield three different types of acidic sugars** depending on the type of oxidizing agent used
| agents used?
Oxidation
## Footnote
Tollen's and Benedict's [weak]
Nitric Acid [strong]
56
**carbonyl group** in a monosaccharide (either an aldose or a ketose) is **reduced to a hydroxyl group** *using hydrogen as the reducing agent*.
Sugar Alcohols
57
general name for **monosaccharide acetals** is
glycoside
58
glucose acetals?
galactose acetals?
glucoside
galactoside
59
an **acetal formed from a cyclic monosaccharide** by **replacement of the hemiacetal carbon -OH group with an -OR group.**
Glycoside
60
Human blood is classified
into four types:
A, B, AB, & O
61
The biochemical basis for the various blood types involves ____ present on ____ .
1. monosaccharides
2. plasma membranes of red blood cells
62
monosaccharides responsible for blood groups:
D-galactose & its derivatives
63
**hydroxyl groups** of a monosaccharide can **react with inorganic oxyacids** to form **inorganic esters**.
Phosphate Ester Formation
64
are **stable in aqueous solution** and **play important roles in the metabolism of carbohydrates.**
Phosphate esters of various monosaccharides
65
**one of the hydroxyl groups** of a monosaccharide is **replaced with an amino group**
Amino Sugar (Formation)
66
important building blocks of polysaccharides:
AMINO SUGARS & their N-acetyl derivatives
67
- the reaction of 2 monosaccharides forms?
disaccharides
68
bond that **links the two monosaccharides of a disaccharide (glycoside) together**
glycosidic linkage
69
- is produced as **an intermediate in the hydrolysis of the polysaccharide cellulose.**
- cannot be digested by humans
Cellobiose
70
Cellobiose contains two ____ units linked through a ____ linkage.
1. b - D-glucose monosaccharide
2. b (1—4) glycosidic
71
- often called **MALT SUGAR**
- produced whenever the **polysaccharide starch breaks down**
## Footnote
as happens in plants when seeds germinate and in human beings during starch digestion.
Maltose
72
Structurally, maltose is made up of ____, one of which must be ____.
1. two D-glucose units
2. a-D-glucose
73
the major sugar found in milk
Lactose
74
Lactose is made up of ____ unit and a ____ unit joined by a ____.
1. b-D-galactose
2. b-D-glucose
3. b (1-4) glycosidic linkage
75
a condition in which **people lack the enzyme lactase** needed to **hydrolyze lactose to galactose and glucose**
Lactose intolerance
76
hydrolyzes b (1-4) glycosidic linkages
Lactase
## Footnote
Deficiency of lactase can be **caused by a genetic defect**, **physiological decline with age, or by injuries to intestinal mucosa.**
77
- table sugar
- most abundant of all disaccharides & found in plants
- produced commercially from the juice of sugar cane and sugar be
- **nonreducing sugars**
Sucrose
78
a **polymer** that contains many monosaccharide units bonded to each other by **glycosidic linkages**.
polysaccharide
79
a polysaccharide in which only **one type of monosaccharide monomer is present**.
homopolysaccharide
80
a polysaccharide in which **more than one (usually two)** type of monosaccharide monomer is present.
heteropolysaccharide
81
is a **polysaccharide that is a storage form for monosaccharides** and is **used as an energy source** in cells
storage polysaccharide
82
- a **homopolysaccharide** containing **only glucose monosaccharide units**.
- the energy-storage polysaccharide in plants
- All of the glycosidic linkages (both *amylose and amylopectin*) are of the a type
## Footnote
they are constantly hydrolyze by ALPHA-AMYLASE
Starch
## Footnote
amylose & amylopectin
83
the other polysaccharide in starch, has a **high degree of branching in its polyglucose structure**.
Amylopectin
84
- like starch, is a polysaccharide **containing only glucose units**
- **Liver cells and muscle cells** are the storage sites
- an **ideal storage form for glucose**
Glycogen
85
- **Linear homopolysaccharide** with b (1-4) glycosidic bond [humans don't have these enzymes that is why they can't digest this]
- It **serves as dietary fiber in food**-- readily absorbs water and results in softer stools.
## Footnote
animals also do not have that enzyme but they can digest it because of their bacteria in the gut.
Cellulose
86
- Similar to cellulose in both function and structure
- **Linear polymer** with all **b (1-4) glycosidic linkages** it has a **N-acetyl amino derivative of glucose**
Chitin
87
polysaccharides with a **repeating disaccharide unit** containing an **amino sugar and a sugar with a negative charge** due to a *sulfate or a carboxyl group*
Acidic polysaccharides
88
Structural polysaccharide present in ____ associated with **joints, cartilage, synovial fluids** in animals and humans
## Footnote
Examples:
* Hyaluronic acid
* Heparin
connective tissue
89
- **Highly viscous** - **serve as lubricants in the fluid of joints** and **part vitreous humor of the eye.**
Hyaluronic acid
90
Alternating residues of Hyaluronic Acid:
1. N-acetyl-b-D-glucosamine
2. D-glucoronic acid
91
An anticoagulant-prevents blood clots
Heparin
92
is a lipid molecule that has **one or more carbohydrate (or carbohydrate derivative) units** covalently bonded to it.
Glycolipids
93
is a **protein molecule that has one or more carbohydrate (or carbohydrate derivative)** units covalently bonded to it.
Glycoproteins
