2 - Carbohydrates

Proverbs 16:3

c. Carbohydrates

Polyhydroxy aldehydes or ketones

a. Lipids
b. Proteins
c. Carbohydrates
d. Nucleic acids

b. "Hydrates of carbon"

In a literal sense, the name carbohydrate can be literally taken as ________

a. "Sugars of life"
b. "Hydrates of carbon"
c. "Carbon of hydrates"
d. "Polyhydroxy ketones"

c. CₙH₂ₙOₙ

[CARBOHYDRATES]

Empirical formula of monosaccharides

a. CₙH₂ₙO₂ₙ
b. C₂ₙHₙOₙ
c. CₙH₂ₙOₙ
d. CₙHₙO₂ₙ

a. True

[CARBOHYDRATES]

Not all carbohydrates are sugars. Sugars should be sweet and includes mono/disaccharides . Polysaccharides like starch are not sweet and cannot be called sugars

a. True

b. False

a. True

[CARBOHYDRATES]

Just like amino acids and proteins, carbohydrates have significance whether they are single units (monosaccharides) or more than that (disaccharides to polysaccharides)

a. True

b. False

• Monosaccharides

• Disaccharides

• Oligosaccharides

• Polysaccharides

Classification of Carbohydrate [4]

• Functional group

• Number of carbons

[CLASSIFICATION OF CARBOHYDRATES]

Monosaccharides can be classified based on _____ [2]

• Aldose

• Ketose

[CLASSIFICATION OF CARBOHYDRATES]

Classification of monosaccharides based on functional group:

a. Triose or tetrose
b. Aldose or ketose
c. Pentose or hexose
d. Furanose or pyranose

• Triose

• Tetrose

• Pentose

• Hexose

[CLASSIFICATION OF CARBOHYDRATES]

Classification of monosaccharides based on number of carbons:

a. Aldose or ketose
b. Triose, tetrose, pentose, hexose
c. D or L configuration
d. Alpha or beta anomer

• Dihydroxyacetone

• Glyceraldehyde

[CLASSIFICATION OF CARBOHYDRATES]

Examples of triose

a. Erythrose, threose
b. Ribose, arabinose
c. Dihydroxyacetone, glyceraldehyde
d. Glucose, galactose, fructose, mannose

• Erythrose

• Threose

[CLASSIFICATION OF CARBOHYDRATES]

Examples of tetrose

a. Dihydroxyacetone, glyceraldehyde
b. Ribose, arabinose
c. Glucose, galactose, fructose, mannose
d. Erythrose, threose

• Ribose

• Arabinose

[CLASSIFICATION OF CARBOHYDRATES]

Examples of pentose

a. Erythrose, threose
b. Ribose, arabinose
c. Dihydroxyacetone, glyceraldehyde
d. Glucose, galactose, fructose, mannose

• Glucose

• Galactose

• Fructose

• Mannose

[CLASSIFICATION OF CARBOHYDRATES]

Examples of hexose

a. Ribose, arabinose
b. Erythrose, threose
c. Dihydroxyacetone, glyceraldehyde
d. Glucose, galactose, fructose, mannose

b. Disaccharides

[CLASSIFICATION OF CARBOHYDRATES]

2 units of carbohydrate

a. Monosaccharides
b. Disaccharides
c. Oligosaccharides
d. Polysaccharides

• Sucrose

• Maltose

• Lactose

📌Mnemonic: “Share Mo Lang”

[CLASSIFICATION OF CARBOHYDRATES]

Examples of disaccharides

a. Raffinose, melezitose, stachyose
b. Cellulose, pectin, chitin
c. Sucrose, Maltose, and Lactose
d. Starch and glycogen

c. Maltose

[CLASSIFICATION OF CARBOHYDRATES]

Disaccharide composed of glucose + glucose

a. Sucrose
b. Lactose
c. Maltose
d. Cellobiose

b. Sucrose

[CLASSIFICATION OF CARBOHYDRATES]

Disaccharide composed of glucose + fructose

a. Maltose
b. Sucrose
c. Lactose
d. Trehalose

c. Lactose

[CLASSIFICATION OF CARBOHYDRATES]

Disaccharide composed of glucose + galactose

a. Sucrose
b. Maltose
c. Lactose
d. Cellobiose

d. Oligosaccharides

[CLASSIFICATION OF CARBOHYDRATES]

3 to 10 units of carbohydrate

a. Polysaccharides
b. Disaccharides
c. Monosaccharides
d. Oligosaccharides

• Raffinose

• Melezitose

• Stachyose

[CLASSIFICATION OF CARBOHYDRATES]

Examples of oligosaccharides

a. Cellulose, pectin, chitin
b. Starch, glycogen
c. Raffinose, melezitose, stachyose
d. Maltose, sucrose, lactose

c. Polysaccharides

[CLASSIFICATION OF CARBOHYDRATES]

More than 10 units of carbohydrate

a. Oligosaccharides
b. Monosaccharides
c. Polysaccharides
d. Disaccharides

►Include most structural carbohydrates

• Cellulose

• Pectin

• Chitin

►Includes stored energy forms for plants and animals

• Starch

• Glycogen

[CLASSIFICATION OF CARBOHYDRATES]

Example of Polysaccharides [2]

d. Starch

[CLASSIFICATION OF CARBOHYDRATES]

Stored energy form of carbohydrates for plants

a. Glycogen
b. Cellulose
c. Chitin
d. Starch

b. Glycogen

[CLASSIFICATION OF CARBOHYDRATES]

Stored energy form of carbohydrates for animals

a. Starch
b. Glycogen
c. Pectin
d. Cellulose

b. Linear

[STRUCTURE & iSOMERISM]

Monosaccharides drawn using Fischer projections

a. Cyclic
b. Linear
c. Branched
d. Pyranose

c. Cyclic

[STRUCTURE & iSOMERISM]

Monosaccharides drawn using Haworth projections

a. Linear
b. Branched
c. Cyclic
d. Open-chain

c. Penultimate OH

[STRUCTURE & iSOMERISM]

The D/L-isomerism is based on this OH

a. Anomeric OH
b. First OH
c. Penultimate OH
d. Glycosidic OH

c. The 2nd to the last carbon

[STRUCTURE & iSOMERISM]

The penultimate carbon refers to _____

a. The first carbon
b. The anomeric carbon
c. The 2nd to the last carbon
d. The carbonyl carbon

c. Aldohexose

[STRUCTURE & iSOMERISM]

Glucose is a polyhydroxy aldehyde, also called this

a. Ketohexose
b. Aldopentose
c. Aldohexose
d. Ketopentose

b. Ketohexose

[STRUCTURE & iSOMERISM]

Fructose is a polyhydroxy ketone, also called this

a. Aldohexose
b. Ketohexose
c. Aldopentose
d. Ketopentose

c. Aldehyde group (CHO)

[STRUCTURE & iSOMERISM]

Functional group at the top of glucose's Fischer projection

a. Hydroxyl group
b. Ketone group
c. Aldehyde group (CHO)
d. Carboxyl group

c. Ketone group (C=O)

[STRUCTURE & iSOMERISM]

Functional group at the top of fructose's Fischer projection

a. Aldehyde group
b. Carboxyl group
c. Ketone group (C=O)
d. Hydroxyl group

c. Hemiacetals

[STRUCTURE & iSOMERISM]

In the process of cyclization, OH⁻ binds with carbonyl, technically making all cyclic monosaccharides

a. Acetals
b. Ketals
c. Hemiacetals
d. Glycosides

b. Furanoses

[STRUCTURE & iSOMERISM]

5-membered rings of cyclic monosaccharides

a. Pyranoses
b. Furanoses
c. Hemiacetals
d. Anomers

c. Pyranoses

[STRUCTURE & iSOMERISM]

6-membered rings of cyclic monosaccharides

a. Furanoses
b. Hemiacetals
c. Pyranoses
d. Anomers

A. True

[STRUCTURE & iSOMERISM]

In order to yield either furanoses or pyranoses, books often use pentoses/hexoses and then use their Penultimate OH

A. True

b. False

[STRUCTURE & iSOMERISM]

Figure 8: Pyranose (left) and furanose (right)

c. Anomeric carbon

[STRUCTURE & iSOMERISM]

What used to be the carbonyl carbon while linear will become _____ while cyclic

a. Penultimate carbon
b. Glycosidic carbon
c. Anomeric carbon
d. Hemiacetal carbon

[STRUCTURE & iSOMERISM]

Figure 9: Beta and alpha anomers of a D-sugar

c. Racemic

[CYCLIZATION]

During cyclization, the OH formed at carbon 1 of glucose is described as

a. Anomeric
b. Penultimate
c. Racemic
d. Hemiacetal

b. B-D-glucopyranose

[CYCLIZATION]

Cyclic Fischer of D-glucose

a. α-D-fructofuranose
b. B-D-glucopyranose
c. D-fructose
d. α-D-glucofuranose

c. Anomeric carbon

[CYCLIZATION]

What used to be the carbonyl carbon (C1) of glucose while linear becomes this while cyclic

a. Penultimate carbon
b. Glycosidic carbon
c. Anomeric carbon
d. Hemiacetal carbon

d. α-D-fructofuranose

[CYCLIZATION]

Cyclization of D-fructose results in this product

a. B-D-glucopyranose
b. D-fructose (linear)
c. Cyclic Fischer of D-glucose
d. α-D-fructofuranose

b. Functional isomerism

[ISOMERISM]

Aldose and ketose is an example of ________

a. Optical isomerism
b. Functional isomerism
c. Diastereomerism
d. Epimerism

b. Optical isomerism

[ISOMERISM]

Changes within the chiral carbons

a. Functional isomerism
b. Optical isomerism
c. Structural isomerism
d. Geometric isomerism

c. Enantiomerism

[ISOMERISM]

All chiral carbons inverted

a. Epimerism
b. Diastereomerism
c. Enantiomerism
d. Functional isomerism

c. Diastereomerism

[ISOMERISM]

Not all chiral carbons inverted

a. Enantiomerism
b. Epimerism
c. Diastereomerism
d. Functional isomerism

c. Epimerism

[ISOMERISM]

Only 1 chiral carbon inverted

a. Diastereomerism
b. Enantiomerism
c. Epimerism
d. Functional isomerism

c. D-Mannose

[ISOMERISM]

✨BEQ: Epimer of D-Glucose at C-2

a. D-Galactose
b. D-Fructose
c. D-Mannose
d. D-Ribose

b. D-Galactose

[ISOMERISM]

Epimer of D-Glucose at C-4

a. D-Mannose
b. D-Galactose
c. D-Fructose
d. D-Ribose

[ISOMERISM]

Figure 10: Epimers of glucose

c. Redox

[REACTIONS & DERIVATIVES]

Generates simple sugar derivatives

a. Hydrolysis
b. Condensation
c. Redox
d. Isomerization

• Oxidation

• Reduction

[REACTIONS & DERIVATIVES]

Redox reaction involves ___ [2]

b. Oxidation

[REACTIONS & DERIVATIVES]

Gives rise to different sugar acids

a. Reduction
b. Oxidation
c. Hydrolysis
d. Condensation

• Uronic acids

• Aldonic acids

• Aldaric acids

[REACTIONS & DERIVATIVES]

Oxidation gives rise to different sugar acids such as _____ [3]

c. Aldonic acids

[REACTIONS & DERIVATIVES]

Oxidation at C1 gives rise to this acid

a. Uronic acids
b. Aldaric acids
c. Aldonic acids
d. Glycosidic acids

c. Aldaric acids

[REACTIONS & DERIVATIVES]

Oxidation at C1 & C6 gives rise to this acid

a. Aldonic acids
b. Uronic acids
c. Aldaric acids
d. Sugar alcohols

d. Uronic acids

[REACTIONS & DERIVATIVES]

Oxidation at C6 gives rise to this acid

a. Aldaric acids
b. Sugar alcohols
c. Aldonic acids
d. Uronic acids

b. Reduction

[REACTIONS & DERIVATIVES]

Gives rise to sugar alcohols

a. Oxidation
b. Reduction
c. Condensation
d. Hydrolysis

c. Hexoses

[REACTIONS & DERIVATIVES]

C6 just means the last carbon, and has always been called C6 because most sugar acids originate from _______

a. Pentoses
b. Trioses
c. Hexoses
d. Tetroses

c. Condensation

[REACTIONS & DERIVATIVES]

This process combines a cyclic sugar to another thing (technically meaning an acetal)

• If the "other thing" is another sugar = Disaccharide

• If the "other thing" is not a sugar = Glycoside

a. Hydrolysis
b. Oxidation
c. Condensation
d. Reduction

b. Disaccharide

[REACTIONS & DERIVATIVES]

Combines a cyclic sugar to another thing (technically meaning an acetal)

• If the "other thing" is another sugar =________

a. Glycoside
b. Disaccharide
c. Polysaccharide
d. Acetal

a. Glycoside

[REACTIONS & DERIVATIVES]

Combines a cyclic sugar to another thing (technically meaning an acetal)

• If the "other thing" is not a sugar = _______

a. Glycoside
b. Disaccharide
c. Polysaccharide
d. Acetal

b. Glycosidic bond

[REACTIONS & DERIVATIVES]

In either case (disaccharide or glycoside), this bond is formed

a. Hydrogen bond
b. Glycosidic bond
c. Peptide bond
d. Ester bond

c. Alpha or beta

[REACTIONS & DERIVATIVES]

In a disaccharide, the glycosidic bond is labelled after the locants of the two carbons connected. If the carbon is anomeric, indicate if __________

a. Cis or trans
b. D or L
c. Alpha or beta
d. R or S

d. Polysaccharide

[REACTIONS & DERIVATIVES]

Condensing more and more sugars together can convert a di- to a tri-, tetra-, and eventually a ________

a. Monosaccharide
b. Oligosaccharide
c. Disaccharide
d. Polysaccharide

c. D-gluconic acid

[REACTION & DERIVATIVES - OXIDATION]

Product of oxidation of D-glucose using weak OA (Cu²⁺) at C1

a. D-glucitol
b. D-glucaric acid
c. D-gluconic acid
d. D-glucuronic acid

c. Cu²⁺

[REACTION & DERIVATIVES - OXIDATION]

Weak OA (oxidizing agent) used in the oxidation of D-glucose at C1

a. HNO₃
b. KMnO₄
c. Cu²⁺
d. H₂O₂

b. D-glucaric acid

[REACTION & DERIVATIVES - OXIDATION]

Product of oxidation of D-glucose using strong OA (HNO₃) at C1 & C6

a. D-gluconic acid
b. D-glucaric acid
c. D-glucuronic acid
d. D-mannitol

d. HNO₃

[REACTION & DERIVATIVES - OXIDATION]

Strong OA (oxidizing agent) used in the oxidation of D-glucose at C1 & C6

a. Cu²⁺
b. O₂
c. H₂O₂
d. HNO₃

c. D-glucuronic acid

[REACTION & DERIVATIVES - OXIDATION]

Product of oxidation of D-glucose using enzymes at C6

a. D-gluconic acid
b. D-glucaric acid
c. D-glucuronic acid
d. D-glucitol

c. [H]

[REACTION & DERIVATIVES - REDUCTION]

Reagent/symbol used to represent reduction

a. [O]
b. OA
c. [H]
d. NAD⁺

c. Mannitol

[REACTION & DERIVATIVES - REDUCTION]

Reduction product of mannose

a. D-glucaric acid
b. Sorbitol
c. Mannitol
d. D-gluconic acid

d. Condensation

[REACTION & DERIVATIVES - CONDENSATION]

Reaction that combines two cyclic sugars with removal of OH and H

a. Hydrolysis
b. Oxidation
c. Reduction
d. Condensation

c. Hydrolysis

[REACTION & DERIVATIVES - CONDENSATION]

Reaction that breaks down a disaccharide using H₂O

a. Condensation
b. Oxidation
c. Hydrolysis
d. Reduction

c. Glycosidic bond

[REACTION & DERIVATIVES - CONDENSATION]

Bond formed when two cyclic sugars undergo condensation

a. Peptide bond
b. Ester bond
c. Glycosidic bond
d. Hydrogen bond

c. Maltose

[REACTION & DERIVATIVES - CONDENSATION]

Disaccharide formed by α 1,4-glycosidic bond between two glucose units

a. Lactose
b. Sucrose
c. Maltose
d. Cellobiose

d. Disaccharide

[REACTION & DERIVATIVES - CONDENSATION]

Two units of a sugar joined together by a glycosidic bond

a. Monosaccharide
b. Polysaccharide
c. Oligosaccharide
d. Disaccharide

a. True

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Knowing the glycosidic bonds can explain their differences in behavior as well as enzymes that hydrolyze them

a. True

b. False

a. True

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Glucose is abbreviated as “glc” and not “glu” ( to avaoid confusion with glutamic acid )

a. True

b. False

• Sucrose

• Maltose

• Lactose

• Cellobiose

• Trehalose

📌Mnemonic: “SML” “CT”

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Table 10: Some common disaccharides include ___ [5]

• Maltose

• Cellobiose

• Lactose

📌Mnemonic: “MCL”

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Disaccharides that have a free reducing end

a. Sucrose and Trehalose
b. Maltose, Cellobiose, and Lactose
c. Maltose and Sucrose
d. Lactose and Trehalose

• Sucrose

• Trehalose

📌Mnemonic: “ST”

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Disaccharides that have no free reducing end

a. Maltose and Cellobiose
b. Lactose and Maltose
c. Sucrose and Trehalose
d. Cellobiose and Lactose

d. Glc-α1,4-Glc

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Glycosidic bond of Maltose

a. Glc-β1,4-Glc
b. Gal-β1,4-Glc
c. Glc-α1,β2-Fru
d. Glc-α1,4-Glc

b. Glc-β1,4-Glc

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Glycosidic bond of Cellobiose

a. Glc-α1,4-Glc
b. Glc-β1,4-Glc
c. Gal-β1,4-Glc
d. Glc-α1,β2-Fru

c. Gal-β1,4-Glc

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Glycosidic bond of Lactose

a. Glc-α1,4-Glc
b. Glc-α1,β2-Fru
c. Gal-β1,4-Glc
d. Glc-α1,α1-Glc

b. Glc-α1,β2-Fru

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Glycosidic bond of Sucrose

a. Glc-β1,4-Glc
b. Glc-α1,β2-Fru
c. Gal-β1,4-Glc
d. Glc-α1,α1-Glc

d. Glc-α1,α1-Glc

[BEYOND MONOSACCHARIDE - DISACCHARIDE]

Glycosidic bond of Trehalose

a. Glc-α1,4-Glc
b. Glc-β1,4-Glc
c. Glc-α1,β2-Fru
d. Glc-α1,α1-Glc

• Homoglycan

• Heteroglycan

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Type of Polysaccharide include ____ [2]

• Starch

• Glycogen

• Cellulose

📌Mnemonic: “SGC”

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Examples of Homoglycan [3]

c. Starch

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Glucan with α1,4 and α1,6 bonds

a. Glycogen
b. Cellulose
c. Starch
d. Chitin

b. Glycogen

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Similar to starch, but with more branches

a. Cellulose
b. Glycogen
c. Chitin
d. Starch

d. Chitin

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Glucan with β1,4 bonds

a. Starch
b. Glycogen
c. Cellulose
d. Chitin

d. Alpha-glucosidase

📌Rationale: Amylase for the initial starch digestion, and Alpha-glucosidase for the final brush border digestion

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

GIT enzyme humans have that digests starch

a. Beta-glucosidase
b. Cellulase
c. Amylase
d. Alpha-glucosidase

b. Beta-glucosidase

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Enzyme humans lack, making cellulose (fiber) indigestible

a. Alpha-glucosidase
b. Beta-glucosidase
c. Amylase
d. Cellulase

• Glycosaminoglycans (GAG) / Mucopolysaccharides (MPS)

• Plant -specific ones like pectin and gums

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Examples of Heteroglycans [2]

c. Glycosaminoglycans (GAG)/Mucopolysaccharides (MPS)

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Contains amino sugars, and are major components of tissues and extracellular matrix

a. Homoglycans
b. Pectin and gums
c. Glycosaminoglycans (GAG)/Mucopolysaccharides (MPS)
d. Starch and glycogen

• Chondroitin

• Hyaluronic acid

• Heparin

📌Mnemonic: “CHH”

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Examples of Glycosaminoglycans (GAG)/Mucopolysaccharides (MPS)

a. Pectin and gums
b. Starch, glycogen, cellulose
c. Maltose, sucrose, lactose
d. Chondroitin, hyaluronic acid, heparin

• Pectin

• Gums

[BEYOND MONOSACCHARIDE - POLYSACCHARIDE]

Plant-specific heteroglycans

a. Chondroitin and heparin
b. Starch and glycogen
c. Pectin and gums
d. Cellulose and chitin

• Energy - either immediate (glucose) or stored (starch in plants, glycogen in animals)

• Structure - cellulose and chitin (cell walls), pectin, etc.

• Pharmaceutical - both carbohydrates and derivatives (e.g. glucose,sucrose, cellulose, starch , etc.)

• Pharmacologic - both carbohydrates and their derivatives (e.g. heparin, lactulose, mannitol, sucralose)

• Nonclinical - especially for cooking or baking

[USES]

Uses of Carbohydrates [5]