p.7
Monosaccharides and Their Isomers
What functional group does glucose contain?
Glucose contains an aldehyde group.
p.28
Sulfated Sugars and Glycosaminoglycans
What family does heparin belong to?
Glycosaminoglycan (GAG) family.
p.3
Types of Carbohydrates
How are carbohydrates produced?
By photosynthesis in plants.
p.22
Modified Sugars: Phosphorylated and Amino Sugars
How are sugar phosphates frequently formed?
By the transfer of a phosphate group (PO4) from ATP.
p.17
Polysaccharides: Structure and Function
What is a polysaccharide?
A sugar containing many (>10) monosaccharide units.
p.7
Monosaccharides and Their Isomers
What type of sugar is glucose?
Glucose is an aldo-hexose sugar.
p.18
Polysaccharides: Structure and Function
What is glycogen?
A branched polysaccharide of glucose.
p.24
Protein Glycosylation and Its Importance
What is protein glycosylation?
The enzyme (glycosyl-transferase) controlled addition of a carbohydrate (modified or otherwise) to the –OH group of a translated protein.
p.11
Monosaccharides and Their Isomers
What forms exist in equilibrium in a solution of monosaccharides?
Straight chain and two cyclic forms.
p.26
Protein Glycosylation and Its Importance
What results in different oligosaccharide chains attached to red blood cell surface proteins?
The activity of different specific glycosyl transferases.
p.14
Glycosidic Bonds and Their Formation
How can glycosidic bonds be broken?
Via enzyme-mediated hydrolytic cleavage.
p.8
Monosaccharides and Their Isomers
What are isomers?
Compounds with the same chemical formula but different structures.
p.31
Bacterial Lipopolysaccharides and Immune Response
What do TOLL-like receptors (TLR4) respond to?
Conserved lipopolysaccharides (LPS) from microbes.
p.9
Monosaccharides and Their Isomers
What are enantiomers?
Isomeric pairs of carbohydrate compounds that are mirror images of each other (D- and L-sugars).
p.28
Sulfated Sugars and Glycosaminoglycans
How are the disaccharide units in heparin joined together?
In a polysaccharide chain.
p.26
Protein Glycosylation and Its Importance
What is the result of different oligosaccharide chains on red blood cell surface proteins?
Different blood types with different cell surface antigens.
p.33
Modified Sugars: Phosphorylated and Amino Sugars
What forms the backbone of DNA?
A repeated pattern of a modified sugar group and a phosphate group.
p.31
Bacterial Lipopolysaccharides and Immune Response
What is the role of TLR4 in the innate immune response?
It activates an inflammatory and immune response.
p.31
Bacterial Lipopolysaccharides and Immune Response
What type of antibodies are produced in response to LPS?
Anti-LPS antibodies that are bactericidal.
p.9
Monosaccharides and Their Isomers
What distinguishes the D-form of a monosaccharide?
The -OH group is bonded to the right of the asymmetric carbon furthest away from the CHO group.
p.8
Monosaccharides and Their Isomers
Which monosaccharides are isomers of each other?
Fructose, glucose, and galactose.
p.7
Monosaccharides and Their Isomers
How many carbon atoms does glucose have?
Glucose has six carbon atoms.
p.3
Types of Carbohydrates
What are carbohydrates?
The most abundant organic molecules in nature.
p.25
Protein Glycosylation and Its Importance
What roles do glycoproteins serve?
They serve a variety of structural and functional roles in membranes and secreted proteins.
p.21
Modified Sugars: Phosphorylated and Amino Sugars
What happens when a phosphate group replaces an -OH group in a monosaccharide?
It forms a phosphorylated sugar, such as glucose-6-phosphate.
p.9
Monosaccharides and Their Isomers
What distinguishes the L-form of a monosaccharide?
The -OH group is bonded to the left of the asymmetric carbon furthest away from the CHO group.
p.21
Modified Sugars: Phosphorylated and Amino Sugars
What is formed when an amino group replaces an -OH group in a monosaccharide?
An amino sugar, such as N-acetylglucosamine.
p.8
Monosaccharides and Their Isomers
What is a key characteristic of monosaccharides in terms of their chemical formula?
They can exist as isomers.
p.22
Modified Sugars: Phosphorylated and Amino Sugars
Why are sugar phosphates important in metabolism?
They play a crucial role in the metabolism of sugars.
p.28
Sulfated Sugars and Glycosaminoglycans
What are the components of the variably sulfated repeating disaccharide unit in heparin?
2-O-sulfated iduronic acid and 6-O-sulfated, N-sulfated glucosamine.
p.3
Types of Carbohydrates
What elements compose carbohydrates and in what ratio?
Carbon, hydrogen, and oxygen in the ratio 1:2:1.
p.18
Polysaccharides: Structure and Function
How is glycogen used to satisfy energy demands?
It is readily converted to glucose as needed.
p.14
Glycosidic Bonds and Their Formation
Are enzymes that hydrolyze glycosidic bonds selective?
Yes, they are selective for specific glycosidic bond types.
p.22
Modified Sugars: Phosphorylated and Amino Sugars
What is the first crucial step in glycolysis?
The phosphorylation of glucose to glucose-6-phosphate by hexokinase.
p.33
Deoxy Sugars and Their Biological Significance
What modification occurs in deoxy-sugars?
Replacing -OH groups with -H groups (removal of oxygen).
p.7
Monosaccharides and Their Isomers
Is glucose a naturally occurring monosaccharide?
Yes, glucose is a naturally occurring monosaccharide.
p.6
Monosaccharides and Their Isomers
What are monosaccharides?
Monosaccharides are single sugar units that form the building blocks of larger carbohydrates.
p.22
Modified Sugars: Phosphorylated and Amino Sugars
What is an example of a sugar phosphorylation in metabolism?
The phosphorylation of glucose to glucose-6-phosphate by hexokinase.
p.11
Monosaccharides and Their Isomers
Why are cyclic forms of monosaccharides less amenable to modifications?
Because they are 'locked' in their structure.
p.24
Protein Glycosylation and Its Importance
What types of sugars can be added during protein glycosylation?
Simple or modified sugars, such as amino sugars and sulfated sugars.
p.22
Modified Sugars: Phosphorylated and Amino Sugars
What does the phosphorylation of glucose facilitate?
The metabolism of glucose to pyruvate.
p.19
Types of Carbohydrates
What happens to blood glucose levels when carbohydrates are consumed and digested?
Blood glucose levels rise.
p.30
Glycolipids and Their Role in Cell Membranes
What are glycolipids?
Lipids with a carbohydrate attached by a glycosidic (covalent) bond.
p.6
Monosaccharides and Their Isomers
What type of group do ketose sugars have and at which carbon?
Ketose sugars have a keto/ketone group at C2.
p.32
Deoxy Sugars and Their Biological Significance
What is an example of a deoxy sugar?
Deoxyribose, or 2-deoxy-D-ribose.
p.27
Sulfated Sugars and Glycosaminoglycans
Give examples of glycosaminoglycans (GAGs).
Chondroitin 6-sulfate, heparan sulfate, dermatan sulfate.
p.23
Modified Sugars: Phosphorylated and Amino Sugars
What is the difference between D-glucosamine and D-glucose?
D-glucosamine has an amino group (NH2) instead of a hydroxyl group (OH) at the second carbon.
p.4
Types of Carbohydrates
What is a common characteristic of many large carbohydrates?
Many large carbohydrates exist as homopolymers and rarely have more than 3-4 different residues.
p.12
Glycosidic Bonds and Their Formation
What is an example of a disaccharide formed by a glycosidic bond?
Maltose, which forms when two alpha-glucose molecules undergo a dehydration synthesis (condensation reaction) to form an alpha 1-4 glycoside bond.
p.12
Glycosidic Bonds and Their Formation
What can monosaccharides form when linked by glycosidic bonds?
They can form disaccharides and straight or branched polysaccharide chains.
p.16
Polysaccharides: Structure and Function
What are polysaccharides?
Carbohydrates that contain more than 10 monosaccharide units linked by glycosidic bonds.
p.1
Glycosidic Bonds and Their Formation
What is a glycosidic bond?
A type of covalent bond that joins a carbohydrate molecule to another group, which can be another carbohydrate.
p.1
Deoxy Sugars and Their Biological Significance
What are deoxy sugars?
Sugars in which a hydroxyl group is replaced by a hydrogen atom, playing important roles in DNA structure and function.
p.2
Sulfated Sugars and Glycosaminoglycans
What is sugar esterification with sulphates and provide an example?
Sugar esterification with sulphates involves the addition of a sulfate group to a sugar molecule. An example is chondroitin sulfate.
p.2
Bacterial Lipopolysaccharides and Immune Response
What is the structure and biological role of bacterial lipopolysaccharide?
Bacterial lipopolysaccharides are large molecules consisting of a lipid and a polysaccharide, playing a crucial role in the immune response.
p.6
Monosaccharides and Their Isomers
What type of group do aldose sugars have and at which carbon?
Aldose sugars have an aldehyde group at C1.
p.24
Protein Glycosylation and Its Importance
Is protein glycosylation a pre-translational or post-translational modification?
Post-translational modification.
p.17
Polysaccharides: Structure and Function
What type of glycosidic bonds are found in starch?
Glc α-1,4 and α-1,6 glycosidic bonds.
p.30
Glycolipids and Their Role in Cell Membranes
Which enzyme catalyzes the formation of glycolipids?
Glycosyltransferase enzymes.
p.27
Sulfated Sugars and Glycosaminoglycans
What enzyme mediates the replacement of a hydroxyl group with a sulfate group to produce sulfated sugars?
Sulfo-transferase enzyme.
p.29
Sulfated Sugars and Glycosaminoglycans
What role does heparin play in blood coagulation?
Heparin activates the main inhibitor of thrombin and factor X – antithrombin III, by an allosteric effect.
p.30
Glycolipids and Their Role in Cell Membranes
What role do glycolipids play in the cell membrane?
They maintain the stability of the cell membrane.
p.5
Monosaccharides and Their Isomers
What are monosaccharides?
Monosaccharides are individual sugars consisting of one sugar molecule.
p.5
Glycosidic Bonds and Their Formation
What are disaccharides?
Disaccharides are carbohydrates consisting of two monosaccharides linked by a glycosidic bond.
p.5
Types of Carbohydrates
List some examples of oligosaccharides.
Raffinose, Heparin, Fructo-oligosaccharides, Galacto-oligosaccharides, Blood group antigens.
p.12
Glycosidic Bonds and Their Formation
What type of bond is formed between two alpha-glucose molecules to create maltose?
An alpha 1-4 glycosidic bond.
p.10
Monosaccharides and Their Isomers
What new asymmetric center is produced during the cyclization of glucose?
An asymmetric center at C1.
p.1
Polysaccharides: Structure and Function
What is the primary function of polysaccharides?
They serve as energy storage (e.g., starch, glycogen) and structural components (e.g., cellulose, chitin).
p.2
Monosaccharides and Their Isomers
What is a monosaccharide and provide an example?
A monosaccharide is the simplest form of carbohydrate, consisting of a single sugar molecule. An example is glucose.
p.2
Modified Sugars: Phosphorylated and Amino Sugars
What is an amino sugar and provide an example?
An amino sugar is a sugar molecule in which a hydroxyl group is replaced by an amino group. An example is glucosamine.
p.32
Deoxy Sugars and Their Biological Significance
What is a deoxy sugar?
A sugar that has had a hydroxyl (-OH) group replaced with a hydrogen atom (-H).
p.14
Glycosidic Bonds and Their Formation
Is amylase active for the Glc β-1-4 glycosidic bond in cellulose?
No, it is inactive for the Glc β-1-4 glycosidic bond in cellulose.
p.21
Glycolipids and Their Role in Cell Membranes
What is formed when a lipid group replaces an -OH group in a monosaccharide?
A glycolipid, such as cerebroside.
p.26
Protein Glycosylation and Its Importance
What extra monosaccharide units are added to Group AB blood type?
N-acetylgalactosamine and galactose are added to separate H proteins.
p.13
Glycosidic Bonds and Their Formation
What do glycosyl transferases specifically catalyze?
The formation of glycoside bonds involving specific sugars (D/L, α/β) and specific OH groups.
p.19
Types of Carbohydrates
What is the role of insulin in glycogen synthesis?
Insulin acts on hepatocytes in the liver to stimulate glycogen synthase.
p.29
Sulfated Sugars and Glycosaminoglycans
How is heparin used in medicine?
Heparin is routinely used as an anticoagulant.
p.29
Sulfated Sugars and Glycosaminoglycans
Why is heparin included in the World Health Organization's List of Essential Medicines?
Because it is an essential anticoagulant.
p.27
Sulfated Sugars and Glycosaminoglycans
Why are sulfate groups on GAGs important for tissues like cartilage?
They make the molecules highly negatively charged, attracting and binding water, which allows tissues to withstand mechanical pressure.
p.5
Polysaccharides: Structure and Function
What are polysaccharides?
Polysaccharides are carbohydrates containing more than ten monosaccharide units.
p.16
Glycosidic Bonds and Their Formation
What are oligosaccharides?
Carbohydrates that contain 3-10 monosaccharides linked by glycosidic bonds.
p.10
Polysaccharides: Structure and Function
What is the most stable subunit of cellulose?
The most stable subunit of cellulose is the β-anomer of glucose.
p.1
Modified Sugars: Phosphorylated and Amino Sugars
What are modified sugars?
Sugars that have been chemically altered, such as phosphorylated sugars and amino sugars.
p.2
Types of Carbohydrates
What is an oligosaccharide and provide an example?
An oligosaccharide is a carbohydrate composed of a small number (typically 3-10) of monosaccharides. An example is raffinose.
p.2
Protein Glycosylation and Its Importance
What is protein glycosylation and why is it biologically important?
Protein glycosylation is the process of adding carbohydrate groups to proteins, which is important for protein folding, stability, and cell signaling.
p.21
Sulfated Sugars and Glycosaminoglycans
What modification occurs when a sulfate group replaces an -OH group in a monosaccharide?
A sulfated sugar, such as heparin, is formed.
p.25
Protein Glycosylation and Its Importance
What do glycan tags contain?
Oligo/polysaccharide glycan tags containing modified sugar units.
p.17
Polysaccharides: Structure and Function
What type of glycosidic bonds are found in glycogen?
Glc α-1,4 and α-1,6 glycosidic bonds.
p.23
Modified Sugars: Phosphorylated and Amino Sugars
What structures do amino sugars constitute part of?
The structure of chitin (insects) and bacterial cell walls.
p.17
Polysaccharides: Structure and Function
What type of glycosidic bonds are found in cellulose?
Glc β-1,4 glycosidic bonds.
p.30
Glycolipids and Their Role in Cell Membranes
Why is cellular recognition facilitated by glycolipids important?
It is crucial to the immune response and in the connections that allow cells to form tissues.
p.27
Sulfated Sugars and Glycosaminoglycans
How can GAGs such as chondroitin sulfate be bonded to proteins?
By glycosyl transferases to form proteoglycan bottle brush structures in cartilage.
p.4
Types of Carbohydrates
How are carbohydrates synthesized?
Carbohydrates are synthesized by enzymes without a template.
p.4
Glycosidic Bonds and Their Formation
What are some types of glycosidic links found in carbohydrates?
Types of glycosidic links include α (1-1), α (1-2), α (1-4), α (1-6), β (1-3), and β (1-4).
p.16
Monosaccharides and Their Isomers
What are monosaccharides?
Individual sugar units that form the building blocks of carbohydrates, such as glucose, fructose, galactose, and mannose.
p.16
Glycosidic Bonds and Their Formation
Give examples of disaccharides.
Sucrose (Glc-Fru), Maltose (Glc-Glc), Lactose (Gal-Glc).
p.10
Glycosidic Bonds and Their Formation
Why are different anomers important?
They are important for glycosidic bond formation and hydrolysis.
p.1
Protein Glycosylation and Its Importance
What is protein glycosylation?
The process by which a carbohydrate is covalently attached to a protein, which is important for protein folding, stability, and cell signaling.
p.2
Types of Carbohydrates
What is a disaccharide and provide an example?
A disaccharide is a carbohydrate composed of two monosaccharides linked by a glycosidic bond. An example is sucrose.
p.2
Deoxy Sugars and Their Biological Significance
What is a deoxy sugar and provide an example?
A deoxy sugar is a sugar molecule in which a hydroxyl group is replaced by a hydrogen atom. An example is deoxyribose.
p.3
Types of Carbohydrates
Do carbohydrates have functions other than providing energy?
Yes, they have many additional biological functions.
p.13
Glycosidic Bonds and Their Formation
What are glycosyl transferases?
Highly specific enzymes that catalyze the formation of specific glycoside bonds.
p.32
Deoxy Sugars and Their Biological Significance
What is the significance of deoxyribose?
It is a constituent of deoxyribonucleotides, the subunits of DNA.
p.15
Glycosidic Bonds and Their Formation
What are disaccharides?
Sugars that contain 2 monosaccharide units linked via a glycosidic bond.
p.13
Glycosidic Bonds and Their Formation
What types of carbohydrates can be formed by glycosyl transferase-catalyzed glycosidic bonds?
Disaccharides, oligosaccharides, and polysaccharides.
p.5
Monosaccharides and Their Isomers
Name four common monosaccharides.
Glucose (Glc), Fructose (Fru), Galactose (Gal), Mannose (Man).
p.4
Types of Carbohydrates
What are the potential building blocks of carbohydrates?
Hexoses and pentoses are potential building blocks of carbohydrates.
p.12
Glycosidic Bonds and Their Formation
What is a glycosidic bond?
A type of covalent bond that joins a carbohydrate (sugar) molecule to another molecule, which may or may not be another carbohydrate.
p.16
Glycosidic Bonds and Their Formation
What is a disaccharide?
A carbohydrate that contains 2 monosaccharide units linked by a glycosidic bond.
p.16
Glycosidic Bonds and Their Formation
Give examples of oligosaccharides.
Raffinose, Galacto-oligosaccharides, Fructo-oligosaccharides, Heparin, Blood group antigens.
p.1
Glycolipids and Their Role in Cell Membranes
What role do glycolipids play in cell membranes?
They contribute to cell recognition, signaling, and membrane stability.
p.2
Glycosidic Bonds and Their Formation
What is a glycosidic bond?
A glycosidic bond is a type of covalent bond that joins a carbohydrate molecule to another group, which can be another carbohydrate.
p.2
Sulfated Sugars and Glycosaminoglycans
What is the structure and biological role of heparin?
Heparin is a sulfated polysaccharide that acts as an anticoagulant, preventing blood clotting.
p.29
Protein Glycosylation and Its Importance
What is blood coagulation dependent upon?
Activation of the clotting cascade.
p.29
Protein Glycosylation and Its Importance
What does the activation of the clotting cascade lead to?
Activation of thrombin which cleaves fibrinogen forming fibrin.
p.27
Sulfated Sugars and Glycosaminoglycans
What are glycosaminoglycans (GAGs) or mucopolysaccharides?
Sulfated sugar chains formed in the extracellular matrix.
p.19
Types of Carbohydrates
What happens to glucose molecules when both blood insulin and glucose levels remain high?
Glucose molecules are added to chains of glycogen.
p.19
Types of Carbohydrates
What is the role of glycogenin in glycogen synthesis?
Glycogenin acts as a primer and starts the polymerization of the first few glucose molecules.
p.19
Types of Carbohydrates
How is glycogenin classified?
Glycogenin is classified as a glycosyltransferase.
p.5
Glycosidic Bonds and Their Formation
Give examples of disaccharides and their monosaccharide components.
Maltose (Glc - Glc), Sucrose (Glc - Fru), Lactose (Glc - Gal).
p.5
Polysaccharides: Structure and Function
Name three common polysaccharides and their glycosidic bonds.
Glycogen (Glc α-1,4 & α-1,6 glycosidic bonds), Cellulose (Glc β-1,4), Starch (Glc α-1,4 & α-1,6 glycosidic bonds).
p.12
Glycosidic Bonds and Their Formation
What enzymes catalyze the formation of glycosidic bonds?
Specific glycosyl transferase enzymes.
p.1
Types of Carbohydrates
What are the main types of carbohydrates?
Monosaccharides, disaccharides, oligosaccharides, and polysaccharides.
p.1
Sulfated Sugars and Glycosaminoglycans
What are glycosaminoglycans?
Long unbranched polysaccharides consisting of repeating disaccharide units that are often sulfated and play a key role in the extracellular matrix.
p.2
Polysaccharides: Structure and Function
What is a polysaccharide and provide an example?
A polysaccharide is a carbohydrate composed of many monosaccharides linked together. An example is glycogen.
p.2
Polysaccharides: Structure and Function
What is the structure and biological role of glycogen?
Glycogen is a highly branched polysaccharide that serves as a form of energy storage in animals.
p.15
Monosaccharides and Their Isomers
Name four common monosaccharides.
Glucose (Glc), Fructose (Fru), Galactose (Gal), Mannose (Man).
p.21
Deoxy Sugars and Their Biological Significance
What is the result of removing an -OH group from a monosaccharide?
A deoxy sugar, such as deoxyribose, is formed.
p.23
Modified Sugars: Phosphorylated and Amino Sugars
What role do amino sugars play in the formation of glycolipids and glycoproteins?
They are used as precursor molecules in glycosyl-transferase-mediated glycosylation.
p.23
Modified Sugars: Phosphorylated and Amino Sugars
What is N-Acetyl-D-glucosamine?
A modified sugar where an acetyl group is attached to D-glucosamine.
p.17
Polysaccharides: Structure and Function
How do starch, glycogen, and cellulose differ?
They differ in the type of glucose present and the bonds which link the glucose monomers together.
p.4
Types of Carbohydrates
What are some structural characteristics of carbohydrates?
Carbohydrates can have poorly defined structures, including helices, branched forms, long chains, and amorphous shapes.
p.5
Types of Carbohydrates
What are oligosaccharides?
Oligosaccharides are carbohydrates consisting of three to ten sugar molecules.
p.12
Glycosidic Bonds and Their Formation
What happens during the formation of a glycosidic bond between two -OH groups on different sugar molecules?
It leads to the loss of a water molecule (dehydration/condensation reaction), leaving sugar/glycosyl residues bonded together by an ether (C-O-C) bond.
p.10
Monosaccharides and Their Isomers
Which hydroxyl group reacts with the aldehyde or keto group during monosaccharide cyclization?
The hydroxyl group on C5.
p.1
Monosaccharides and Their Isomers
What is a monosaccharide?
A simple sugar that cannot be hydrolyzed to give a simpler sugar.
p.1
Bacterial Lipopolysaccharides and Immune Response
What are bacterial lipopolysaccharides?
Molecules found in the outer membrane of Gram-negative bacteria that can trigger strong immune responses in humans.
p.2
Modified Sugars: Phosphorylated and Amino Sugars
What is sugar esterification with phosphates and provide an example?
Sugar esterification with phosphates involves the addition of a phosphate group to a sugar molecule. An example is glucose-6-phosphate.
p.2
Sulfated Sugars and Glycosaminoglycans
What is the structure and biological role of proteoglycan?
Proteoglycans are proteins heavily glycosylated with glycosaminoglycans, playing a key role in the structure of connective tissues.
