BCM Quiz 5 (Ch. 11, 12, 13, 15)

What term describes molecules that have both hydrophilic and hydrophobic moieties?

amphoteric

amphiprotic

amphibian

amphipathic

amphiapomictic

amphipathic

What membrane components contain carbohydrates?

lipid-linked proteins

cholesterol

integral membrane proteins in contact with the cytoplasm

phosphatidylserine

glycolipids

glycolipids

Select all that apply. Membranes are primarily comprised of:

lipids.

proteins.

carbohydrates.

metals.

water.

lipids.

proteins.

What statement about membranes is INCORRECT?

Membranes are lipid bilayers.

Membrane consists of peptides and lipids.

Many membranes are electrically polarized.

Membrane is an absolutely solid formation.

Membrane lipids have both hydrophobic and hydrophilic properties.

Membrane is an absolutely solid formation.

The MOST fluid membrane would be a bilayer made of lipids with:

polyunsaturated 18-carbon fatty acids.

saturated 18-carbon fatty acids.

saturated 16-carbon fatty acids.

polyunsaturated 16-carbon fatty acids.

polyunsaturated 20-carbon fatty acids.

polyunsaturated 16-carbon fatty acids.

What statement is consistent with the structure of biological membranes?

All membrane proteins are integral and associate with the hydrophobic region of the membrane.

Both proteins and lipids readily undergo transverse ("flip-flop") diffusion.

Membranes are symmetric.

The membrane lipids self-assemble to form the lipid bilayer.

A biological membrane consists of proteins sandwiched between two layers of lipids.

The membrane lipids self-assemble to form the lipid bilayer.

Carbohydrate residues attached to the membrane lipids are almost always:

positioned on the intracellular side of the membrane.

positioned on the inside center of the bilayer.

positioned on the extracellular side of the membrane.

positioned equally on both sides of the membrane.

also covalently attached to membrane proteins.

positioned on the extracellular side of the membrane.

What forces stabilize the lipid bilayers? Select all that apply.

van der Waals interactions

electrostatic bonding between the polar heads and surrounding water

covalent bonds between the lipids and membrane proteins

disulfide bridges between the membrane proteins

hydrogen bonding between the polar heads and surrounding water

van der Waals interactions

electrostatic bonding between the polar heads and surrounding water

hydrogen bonding between the polar heads and surrounding water

An external cell membrane of eukaryotic cells is called:

endoplasmic reticulum.

cell wall.

plasma membrane.

nuclear envelope.

planar bilayer membrane.

plasma membrane.

What statement about fatty acids is INCORRECT?

Fatty acid carbon atoms are numbered starting at the carboxyl terminus.

A cis-Δ2 means that there is a cis double bond between carbon atoms 2 and 3.

A double bond can be denoted by counting from the distal end, with the ω-carbon atom.

Carbon atoms 2 and 3 are often referred to as α and β, respectively.

Fatty acids in biological systems usually contain an odd number of carbon atoms.

Fatty acids in biological systems usually contain an odd number of carbon atoms.

Arrange the following fatty acids in order of increasing melting point: palmitic acid (C16, 1 double bond), stearic acid (C18, 0 double bond), oleic acid (C18, 1 double bond).

palmitic acid, stearic acid, oleic acid

oleic acid, palmitic acid, stearic acid

stearic acid, palmitic acid, oleic acid

The melting point of these fatty acids is equal.

There is not enough data to determine the melting point.

oleic acid, palmitic acid, stearic acid

What is the major class of membrane lipids?

phospholipids

glycolipids

cholesterol

sphingolipids

ceramides

phospholipids

What kind of lipids consist of at least one fatty acid, a platform to which the fatty acids are attached, a phosphate, and an alcohol attached to the phosphate?

phospholipids

glycolipids

cholesterol

gangliosides

sphingolipids

phospholipids

Select all that apply. Amphipathic properties of membrane lipids are provided by a:

hydrophilic hydrocarbon tale.

hydrophobic head.

hydrophobic hydrocarbon tale.

hydrophilic head.

nonpolar head.

hydrophobic hydrocarbon tale.

hydrophilic head.

Which structures are composed of aqueous compartments enclosed by a lipid bilayer and can be used to deliver chemicals to cells?

micelle

vesicle

lysosome

chloroplast

ribosome

vesicle

Arrange the following structures in order of increasing dimensions.

micelle, lipid bilayer, vesicle

vesicle, micelle, lipid bilayer

lipid bilayer, vesicle, micelle

micelle, vesicle, lipid bilayer

lipid bilayer, micelle, vesicle

micelle, vesicle, lipid bilayer

Select all that apply. "Integral" membrane proteins are:

proteins that traverse the lipid bilayer.

membrane proteins that interact extensively with the hydrocarbon chains of membrane lipids.

membrane proteins that can be released only by agents that compete for nonpolar interactions of the protein and the hydrocarbon chains of membrane lipids.

proteins that connect with membrane lipids via polar interactions.

proteins that are loosely bonded with the membrane.

proteins that traverse the lipid bilayer.

membrane proteins that interact extensively with the hydrocarbon chains of membrane lipids.

membrane proteins that can be released only by agents that compete for nonpolar interactions of the protein and the hydrocarbon chains of membrane lipids.

What statement about "peripheral" membrane proteins is INCORRECT??

They are membrane proteins that interact with the polar head groups of the membrane lipids.

They are membrane proteins that bind to the surfaces of integral proteins.

They are membrane proteins that are anchored to the membrane by a covalently attached lipid molecule.

Polar interactions of peripheral protein and polar head groups of the membrane lipids can be disrupted by adding salts or by changing the pH.

They are membrane proteins that traverse the lipid bilayer.

They are membrane proteins that traverse the lipid bilayer.

What property is NOT a characteristic of the biological membranes?

organization of biological membranes is described as a fluid mosaic model

membrane has the transverse diffusion of its lipids

membrane has the lateral diffusion of its components

membranes are two-dimensional solutions of oriented lipids and globular proteins

membrane is always impenetrable

membrane is always impenetrable

Lateral diffusion is:

spontaneous fast rotation of lipids from one face of a membrane to the other.

fast diffusion of proteins and lipids across the membrane.

diffusion of proteins across the membrane.

spontaneous slow rotation of lipids from one face of a membrane to the other.

slow diffusion of proteins and lipids across the membrane.

fast diffusion of proteins and lipids across the membrane.

Transverse diffusion is:

fast rotation of lipids from one face of a membrane to the other.

flip-flop of membrane proteins.

slow rotation of lipids from one face of a membrane to the other.

fast diffusion of proteins and lipids across the membrane.

slow diffusion of proteins and lipids across the membrane.

slow rotation of lipids from one face of a membrane to the other.

What substance is the key regulator of membrane fluidity in animals?

cholesterol

glycerol

inositol phosphate

cerebroside

sphingomyelin

cholesterol

Plant cells have:

two membranes separated by a cell wall.

membranes consisting of a single lipid bilayer.

cell wall on the outside of the plasma membrane.

cell wall surrounded by a plasma membrane.

membrane consisting of proteins.

cell wall on the outside of the plasma membrane.

What is the major difference between eukaryotic and prokaryotic cells?

Eukaryotic cell membranes consist of a single lipid bilayer.

Prokaryotic cells do not have cell walls.

Eukaryotic cells have membranes inside the cell that form internal compartments.

Prokaryotic cells have periplasm.

Prokaryotic cells have membranes that consist of two lipid bilayers.

Eukaryotic cells have membranes inside the cell that form internal compartments.

What structure is surrounded by two membranes and is responsible for ATP synthesis?

nuclear envelope

mitochondria

nucleus

peroxisome

endoplasmic reticulum

mitochondria

What structure takes part in drug detoxification and the modification of proteins?

nuclear envelope

endoplasmic reticulum

vesicle

mitochondria

peroxisome

endoplasmic reticulum

In which processes does the membrane take part? Select all that apply.

separating compartments

joining compartments together

transport of molecules

release of molecules

storage of molecules

separating compartments

joining compartments together

transport of molecules

release of molecules

What proteins take part in receptor-mediated endocytosis?

clathrin

transferrin

myoglobin

hemocyanin

proton pumps

clathrin

_______ interactions are the major driving force for the formation of lipid bilayers.

Hydrophobic

What molecule structures allow for permeability of biological membranes? Select all that apply.

pumps

carriers

channels

tubes

tunnels

pumps

carriers

channels

How does energy affect the functioning of the Na+-K+ ATPase? Select all that apply.

ATP provides energy for this pump to function.

The pump maintains the proper cellular concentration of Na+ and K+.

Without ATP, the pump would not be able to function.

Without ATP, the pump transport only K+.

The pump maintains only the proper cellular concentration of Na+.

ATP provides energy for this pump to function.

The pump maintains the proper cellular concentration of Na+ and K+.

Without ATP, the pump would not be able to function.

What channels does tetrodotoxin isolated from the puffer fish bind to?

Na+ channels

K+ channels

Na+ and Ca2+

K+ and Ca2+ channels

anion channels

Na+ channels

What channel opens in response to binding of a particular molecule?

voltage-gated

ligand-gated

active diffusion

passive diffusion

ABC transporter

ligand-gated

What channel opens in response to membrane depolarization?

ion-gated

ligand-gated

voltage-gated

active diffusion

passive diffusion

voltage-gated

What are the main features of simple diffusion?

Molecules pass through a membrane from areas of lower to higher concentration. Only lipophilic molecules can easily pass through the membrane.

Molecules pass through a membrane from areas of higher to lower concentration. Only hydrophilic molecules can easily pass through the membrane.

Molecules pass through a membrane from areas of higher to lower concentration. Only lipophilic molecules can easily pass through the membrane.

Molecules pass through a membrane from areas of lower to higher concentration. Only hydrophilic molecules can easily pass through the membrane.

Molecules pass through a membrane from areas of lower to higher concentration. Only nonpolar molecules can easily pass through the membrane.

Molecules pass through a membrane from areas of higher to lower concentration. Only lipophilic molecules can easily pass through the membrane.

Ion channels:

are not selective.

exist only in open state.

can be selective and exist in open and closed states.

are not selective and exist in open and closed states.

can be selective and exist only in open state.

can be selective and exist in open and closed states.

What amino acid determines ion selectivity of the Ca2+ channel?

aspartate

glutamate

lysine

alanine

glycine

glutamate

What clues provide evidence of the mechanism of channel inactivation? Select all that apply.

Inactivation can be restored by the addition of part of a missing peptide.

Proteolysis of the cytoplasmic side leads to permanent open channel.

Mutations in amino acid sequence leads to differences in inactivation kinetics.

Peptide denaturation leads to permanent open channel.

Proteolysis of the extracellular side leads to permanent open channel.

Inactivation can be restored by the addition of part of a missing peptide.

Proteolysis of the cytoplasmic side leads to permanent open channel.

Mutations in amino acid sequence leads to differences in inactivation kinetics.

What molecules are responsible for sending nerve impulses?

tetrodotoxin

acetylcholine

cobratoxin

connexin

cefazolin

acetylcholine

What is the differences between active and passive transport?

Active transport requires an external energy source.

Passive transport takes place when a molecule moves against its concentration gradient.

Passive transport results in the generation of concentration gradients.

Active transport takes place when a molecule moves down its concentration gradient.

Passive transport is present only in the human cells.

Active transport requires an external energy source.

How does SERCA regulate muscle activity?

An increase in Ca2+ ions causes muscle constriction, and a decrease in Ca2+ ions causes muscle relaxation.

A decrease in Ca2+ ions causes muscle constriction, and an increase in Ca2+ ions causes muscle relaxation.

An increase in K+ ions causes muscle constriction, and a decrease in K+ ions causes muscle relaxation.

A decrease in K+ ions causes muscle constriction, and an increase in K+ ions causes muscle relaxation.

A increase in K+ ions causes muscle constriction, and an decrease in Ca2+ ions causes muscle relaxation.

An increase in Ca2+ ions causes muscle constriction, and a decrease in Ca2+ ions causes muscle relaxation.

Name the consequences of Na+-K+ pump inhibition. Select all that apply.

The intracellular level of Na+ ions increases.

Ca2+ extrusion slows down.

An increase in the Ca2+ intracellular level leads to an increase in the ability of cardiac muscle to contract.

The intracellular level of K+ decreases.

The extracellular level of K+ decreases.

The intracellular level of Na+ ions increases.

Ca2+ extrusion slows down.

An increase in the Ca2+ intracellular level leads to an increase in the ability of cardiac muscle to contract.

Carrier proteins:

transport ions or molecules across the membrane without hydrolysis of ATP.

mediate primary active transport.

utilize the gradient of one ion to drive the transport of another ion down its concentration gradient.

provide translocation across the membrane only for molecules.

have two classes: uniporters and symporters.

transport ions or molecules across the membrane without hydrolysis of ATP.

What processes underlie the nerve impulse?

depolarization of the membrane from -60 to -40mV, an increase in Na+ permeability, intracellular accumulation of Na+ ions

repolarization of the membrane to +30mV, spontaneous permeability switch from K+ to Na+

the release of Na+ ions from the cell causes transition from the repolarization state to the polarization state

the release of Cl- ions from the cell causes depolarization of membrane from -80 to - 120 mV

the release of K+ ions from the cell causes transition from the repolarization state to the depolarization state

depolarization of the membrane from -60 to -40mV, an increase in Na+ permeability, intracellular accumulation of Na+ ions

What process takes place right after the nerve impulse arrives at the end of the axon?

binding of acetylcholine to the postsynaptic membrane

depolarization of the presynaptic membrane

export of acetylcholine vesicles into the synaptic cleft

repolarization of the presynaptic membrane

import of adrenaline vesicles into the postsynaptic membrane

export of acetylcholine vesicles into the synaptic cleft

An acetylcholine receptor is permeable for:

Na+ and Ca2+.

Na+ and K+.

K+ and Ca2+.

Mg2+.

Cl-.

Na+ and K+.

What channels do not transport ions at all?

aquaporins

acetylcholine receptors

ligand-gated channels

voltage-gated channels

ABC transporters

aquaporins

Select all that apply. Membrane potential is:

the sum of concentrations and electric terms.

electrochemical potential.

the sum of charged and uncharged molecules passing through channels.

the sum of all polar molecules passing through channels and back.

the sum of all nonpolar molecules passing through channels and back.

the sum of concentrations and electric terms.

electrochemical potential.

What are CORRECT statements about the binding sites of membrane pumps? Select all that apply.

The external site can be open or closed while the internal site is open.

The internal site can be open or closed while the external site is open.

The external and internal sites are always open.

The external site is open while the internal site is closed.

The internal site is open while the external site is closed.

The external site is open while the internal site is closed.

The internal site is open while the external site is closed.

When an uncharged molecule moves against the concentration grade, the process is:

at equilibrium.

in need of energy resources.

spontaneous.

dependent on membrane potential.

stopped anyway.

in need of energy resources.

Why can Na+ NOT pass through a potassium channel?

The Na+ ion radius is larger than the K+ ion radius.

The Na+ ion radius is larger than 3 Ǻ.

The Na+ ion radius is smaller than the K+ ion radius.

The Na+ ion radius is equal to 3 Ǻ.

The Na+ ion radius is smaller than 3 Ǻ.

The Na+ ion radius is smaller than the K+ ion radius.

Fuels are degraded and large molecules are constructed step by step in a series of linked reactions. What type of reaction corresponds to this statement?

cellular respiration

photosynthesis

catabolic reaction

metabolic pathway

oxidation

metabolic pathway

Where does fatty acid oxidation occur?

the cytoplasm

the Golgi apparatus

mitochondria

plastids

lysosomes

mitochondria

What type of reactions requires energy?

anabolic

catabolic

biochemical

chemical

spontaneous

anabolic

Select all that apply. The ΔG of reactions depends on:

temperature.

enzymes.

nature of the reactants.

free energy.

nature of the products.

nature of the reactants

nature of the products.

The total free-energy change for a chemically related series of reactions equals the:

sum of the free-energy changes of individual steps.

difference of the free-energy changes between each individual step.

difference of the free-energy changes of all steps.

free-energy changes of an individual step.

maximum free energy.

sum of the free-energy changes of individual steps.

A thermodynamically unfavorable reaction is driven by:

a thermodynamically favorable reaction to which it is coupled.

free energy.

a catabolic reaction.

a favorable reaction.

an anabolic reaction.

a thermodynamically favorable reaction to which it is coupled.

What does ATP contain?

ribose

orthophosphate

deoxyribose

metal ions

adenylate

ribose

What is the primary role of catabolism?

generation of complex structures from simple ones

generation of ATP

generation of acetyl CoA

degradation of biomolecules

active transport

generation of ATP

What bond attaches an acetyl group to coenzyme A?

thioester bond

anhydride bond

phosphoanhydride bond

covalent bond

carbon bond

thioester bond

What accepts a hydrogen ion and two electrons in the oxidation of a substrate?

the nicotinamide ring of NAD+

the reactive part of FAD

FADH2

acetyl CoA

ATP

the nicotinamide ring of NAD+

What is the ultimate product of oxidation in aerobic organisms?

O2

H2O

pyruvate

CO2

lactate

CO2

How is NADPH different from NADH? Choose the statement that is correct for NADPH.

The reactive part of NADH is its nicotinamide ring.

The nitrogen atom carries a positive charge.

NADPH carries high-potential electrons.

Its adenosine moiety is esterified with phosphate.

It is used primarily for the generation of ATP.

Its adenosine moiety is esterified with phosphate.

What group forms the reactive site of coenzyme A?

sulfhydryl

acyl

amino

carboxyl

carbonyl

sulfhydryl

What organic molecules are the sources of coenzymes in some higher animals?

proteins

lipids

vitamins

carbohydrates

minerals

vitamins

What vitamin regulates calcium and phosphate metabolism?

C

B6

E

D

K

D

Scurvy, a disease characterized by skin lesions and blood-vessel fragility, is caused by the deficiency of vitamin:

A.

B12.

C.

D.

E.

C.

The reaction of rearrangement of atoms to form isomers is:

oxidation-reduction.

group transfer.

hydrolytic.

isomerization.

ligation requiring ATP cleavage.

isomerization.

What enzymes catalyze reactions where carbon bonds are cleaved by means other than hydrolysis or oxidation?

lyases

catalases

kinases

phosphatases

isomerases

lyases

What reactions rearrange particular atoms within a molecule while conserving the empirical formula?

isomerization

ligation

group transfer

oxidation-reduction

hydrolysation

isomerization

Metabolic processes are regulated by:

transcriptional regulation of the amount of enzyme.

allosteric control of enzyme activity.

accessibility of substrates by compartmentalization.

covalent modification of enzymes.

All of the answers are correct.

All of the answers are correct.

The product of the second stage of catabolism is:

acetyl CoA.

ATP.

CO2.

H2O.

O2.

acetyl CoA.

What substance serves as the electron donor for most reductive biosynthetic pathways?

NADPH

NADH

FAD

FMN

NAD+

NADPH

Why does acetyl CoA have a high acetyl-group-transfer potential?

Coenzyme A carries the terminal sulfhydryl group.

Acetyl CoA carries an activated phosphoryl group.

The transfer of the acetyl group is exergonic.

The transfer of the acetyl group is endergonic.

The transfer of the other groups is unfavorable.

The transfer of the acetyl group is exergonic.

Reaction pathways that exclusively transform fuels into cellular energy are:

anabolic.

catabolic.

allobolic.

amphibolic.

metabolic.

catabolic.

Which cellular process(es) require energy?

performance of mechanical work

facilitated diffusion

degradation of biomolecules

active transport

performance of mechanical work and active transport

performance of mechanical work and active transport

The phosphoryl-transfer potential of ATP is lower than that of:

pyrophosphate.

creatine phosphate.

2,3-bisphosphoglycerate.

glucose 1-phosphate.

glucose 6-phosphate.

creatine phosphate.

What is the ultimate electron acceptor in aerobic organisms?

carbon dioxide

NAD+

FAD

oxygen

succinate

oxygen

What metabolic reaction type involves a cleavage of bonds by the addition of water?

ligation

isomerization

group transfer

oxidation-reduction

hydrolyzation

hydrolyzation

What compound serves as an acyl carrier in metabolism?

FAD

biotin

thiamine pyrophosphate

coenzyme A

tetrahydrofolate

coenzyme A

The reduced form of flavin adenine dinucleotide is:

FADH.

FAD.

FADH++.

FADH2.

FAD+.

FADH2.

The electron carrier _______ is derived from the vitamin riboflavin.

FAD

Which statement does NOT apply to carbohydrates and carbohydrate-associated proteins?

 

Carbohydrates provide cell-to-cell communication.

 

Carbohydrates, carbohydrate-containing proteins, and carbohydrate-binding proteins allow formation of tissues by cells.

 

Carbohydrates supply details and enhancements to the biological architecture of the cell.

 

Carbohydrate-containing and carbohydrate-binding proteins catalyze biochemical reactions in the organism.

 

Carbohydrates, carbohydrate-containing proteins, and carbohydrate-binding proteins define human blood groups.

Carbohydrate-containing and carbohydrate-binding proteins catalyze biochemical reactions in the organism.

What accounts for the wide range of carbohydrate functions?

 

involvement in metabolism

 

stability of molecules

 

hydrophobic property

 

hydrophilic property

 

structural diversity

structural diversity

What are constitutional isomers?

 

carbohydrates that have identical molecular formulas but differ in how the atoms are ordered

 

carbohydrates that have different molecular formulas and differ in how the atoms are ordered

 

carbohydrates that have identical molecular formulas but different spatial arrangements

 

carbohydrates that have identical molecular formulas and look like mirror images of each other

 

carbohydrates that have identical molecular formulas but a different asymmetric carbon atom in the closed ring structure

carbohydrates that have identical molecular formulas but differ in how the atoms are ordered

Calculate the number of possible stereoisomers of an aldose with two asymmetric carbon atoms.

 

2

 

3

 

4

 

5

 

6

4

What type of sugar is fructose?

 

heptose

 

hexose

 

pentose

 

tetrose

 

triose

hexose

What is the chemical basis for the cyclization of sugars in solution?

 

interaction of hydroxyl groups with each other

 

formation of peptide bonds between carbon atoms and nitrogen atoms in modified sugars

 

reaction between the aldehyde group of one sugar molecule and the aldehyde group of another sugar molecule

 

formation of hydrogen bonds between sugar and water molecules

 

reaction of the carbonyl group with an alcohol group

reaction of the carbonyl group with an alcohol group

Glucose molecules form an intramolecular hemiacetal through the interaction of the:

 

C-5 hydroxyl group and the C-1 carbon of the aldehyde group.

 

C-4 hydroxyl group and the C-1 carbon of the aldehyde group.

 

C-3 hydroxyl group and the C-1 carbon of the aldehyde group.

 

C-2 hydroxyl group and the C-5 hydroxyl group.

 

C-3 hydroxyl group and the C-6 hydroxyl group.

C-5 hydroxyl group and the C-1 carbon of the aldehyde group.

Which pair of carbohydrates is epimeric at C-2?

 

 

 

 

 

In the figure, which numbered bonds define the glycosidic bond? Select all that apply.

 

1

 

2

 

3

 

4

 

5

3 and 4

What carbohydrate is an essential energy source for virtually all forms of life?

 

fructose

 

cellulose

 

glucose

 

galactose

 

starch

glucose

Why is corn syrup with a high concentration of fructose in the β-D-pyranose form used as a sweetener in cold, but not hot, drinks?

 

Heating leads to decyclization and eventually degrades the molecule.

 

Heating makes corn syrup bitter without causing any conformational changes.

 

Heating converts sweet β-glucopyranose to the tasteless α-glucopyranose form.

 

Heating converts sweet β-fructopyranose into the bitter β-glucopyranose form.

 

Heating converts sweet β-fructopyranose into the less sweet β-fructofuranose form.

Heating converts sweet β-fructopyranose into the less sweet β-fructofuranose form.

Which structure depicts β-D-ribofuranose?

 

 

 

 

 

What distinguishes D and L isomers?

 

configuration of the carbonyl group

 

configuration of the second carbon atom from the aldehyde or keto group

 

configuration of the asymmetric carbon atom farthest from the aldehyde or keto group

 

configuration of all the hydroxyl groups

 

charge of the molecule

configuration of the asymmetric carbon atom farthest from the aldehyde or keto group

What are the consequences of sugar phosphorylation? Select all that apply.

 

Sugars gain a negative charge.

 

Sugars gain a positive charge.

 

The gained charge prevents spontaneous interaction of modified sugars with transporters of the unmodified sugar.

 

Phosphorylation creates intermediates that are less available for metabolic reactions.

 

The gained charge causes sugars to leave the cell by crossing the lipid bilayer membrane.

Sugars gain a negative charge.

The gained charge prevents spontaneous interaction of modified sugars with transporters of the unmodified sugar.

Maltose is a disaccharide composed of:

 

α-D-glucopyranose and β-D-fructofuranose.

 

α-D-galactopyranose and α-D-glucopyranose.

 

α-D-glucopyranose and α-D-glucopyranose.

 

β-D-fructofuranose and α-D-galactopyranose.

 

β-D-glucopyranose and β-D-fructofuranose.

α-D-glucopyranose and α-D-glucopyranose.

What property of reducing sugars is used to assess the effectiveness of treatments for diabetes mellitus?

 

ability to dissolve in polar solvents

 

ability to react with and form a covalent bond with a free amino group of hemoglobin

 

ability to avoid reactions with amino acids of hemoglobin by forming a ring

 

ability to prevent a rise in the blood glucose level by binding with specific diabetes factors

 

ability to induce the proliferation of red blood cells

ability to react with and form a covalent bond with a free amino group of hemoglobin

Where in the cell are glycoproteins and glycolipids commonly located?

 

external surface of the plasma membrane

 

Golgi complex

 

lumen of the ER

 

inner surface of the plasma membrane

 

ER membrane

external surface of the plasma membrane

What monosaccharide lacks an asymmetric carbon atom?

 

fructose

 

mannose

 

altrose

 

galactose

 

dihydroxyacetone

dihydroxyacetone