Question 1

When electron micrographs were first taken of the cell interior, what kinds of structures were seen?

Accepted Answer

A) membrane-bound vesicles of varying diameter, containing material of different electron density 
B) long channels bounded by membranes and radiating through the cytoplasm 
C) an interconnected network of canals 
D) stacks of flattened, membrane-bound sacs called cisternae 
E) all of these are correct 
A) membrane-bound vesicles of varying diameter, containing material of different electron density 
B) long channels bounded by membranes and radiating through the cytoplasm 
C) an interconnected network of canals 
D) stacks of flattened, membrane-bound sacs called cisternae 
E) all of these are correct

Question 2

Why does the cell use proteasomes to destroy misfolded proteins?

Accepted Answer

A) Destruction of misfolded proteins assures that aberrant proteins are not sent to other parts of the cell. 
B) These proteins can be degraded into components that can be used to make polynucleotides. 
C) These proteins are degraded into components that can be used to make polysaccharides. 
D) These proteins are degraded into components that are used to make lipids. 
E) Destruction of misfolded proteins prevents the dissolution of the plasma membrane. 
A) Destruction of misfolded proteins assures that aberrant proteins are not sent to other parts of the cell. 
B) These proteins can be degraded into components that can be used to make polynucleotides. 
C) These proteins are degraded into components that can be used to make polysaccharides. 
D) These proteins are degraded into components that are used to make lipids. 
E) Destruction of misfolded proteins prevents the dissolution of the plasma membrane.

Question 3

Where is this common domain of SNAREs located, of what is it composed and what is it called?

Accepted Answer

A) in the lumen, 60 - 70 amino acids that form a complex with another SNARE motif 
B) in the lumen, 60 - 70 nucleotides that form a complex with another SNARE motif 
C) in the cytosol, 60 - 70 amino acids that form a complex with another SNARE motif 
D) in the cytosol, 60 - 70 amino acids forming a complex with another SNARE coil 
E) in the cytosol, 60 - 70 carbohydrates forming a complex with another SNARE motif 
A) in the lumen, 60 - 70 amino acids that form a complex with another SNARE motif 
B) in the lumen, 60 - 70 nucleotides that form a complex with another SNARE motif 
C) in the cytosol, 60 - 70 amino acids that form a complex with another SNARE motif 
D) in the cytosol, 60 - 70 amino acids forming a complex with another SNARE coil 
E) in the cytosol, 60 - 70 carbohydrates forming a complex with another SNARE motif

Question 4

What allows smooth and rough vesicles (microsomes)to be readily separated by density gradient centrifugation?

Accepted Answer

A) their size differences 
B) their differences in lipid composition 
C) their differences in color 
D) their differences in density 
E) their differences in water content 
A) their size differences 
B) their differences in lipid composition 
C) their differences in color 
D) their differences in density 
E) their differences in water content

Question 5

When Rabs have bound to GTP, what do they do?

Accepted Answer

A) They fuse membranes directly. 
B) They pass through the membrane. 
C) They recruit specific cytosolic tethering proteins to specific membrane surfaces. 
D) They denature specific membrane proteins. 
E) They fuse to the nuclear membrane. 
A) They fuse membranes directly. 
B) They pass through the membrane. 
C) They recruit specific cytosolic tethering proteins to specific membrane surfaces. 
D) They denature specific membrane proteins. 
E) They fuse to the nuclear membrane.

Question 6

What is thought to shield lysosomal membranes against attack by their enclosed enzymes?

Accepted Answer

A) DNA 
B) basic RNA 
C) carbohydrate chains attached to integral membrane proteins 
D) carbohydrate chains attached to peripheral membrane proteins 
E) the lipid bilayer itself 
A) DNA 
B) basic RNA 
C) carbohydrate chains attached to integral membrane proteins 
D) carbohydrate chains attached to peripheral membrane proteins 
E) the lipid bilayer itself

Question 7

What determines the sequence of sugar addition to glycoproteins traveling through the Golgi complex?

Accepted Answer

A) Nothing - the sequence is random. 
B) the spatial arrangement of specific glycosyltransferases that contact proteins as they pass through the Golgi complex 
C) the concentration of sugars in the Golgi complex 
D) the concentration of proteins in the Golgi complex 
E) the sequence of nucleotides in the Golgi complex 
A) Nothing - the sequence is random. 
B) the spatial arrangement of specific glycosyltransferases that contact proteins as they pass through the Golgi complex 
C) the concentration of sugars in the Golgi complex 
D) the concentration of proteins in the Golgi complex 
E) the sequence of nucleotides in the Golgi complex

Question 8

Which GTP-binding protein plays a regulatory role by initiating vesicle formation and by regulating the assembly of the vesicle's COPII coat?

Accepted Answer

A) Sar1 
B) Gar1 
C) ARF1 (adenosylation ribose factor) 
D) Ras 
E) Src 
A) Sar1 
B) Gar1 
C) ARF1 (adenosylation ribose factor) 
D) Ras 
E) Src

Question 9

Which components below are selected for transport by vesicles originating in the Golgi complex?

Accepted Answer

A) secretory proteins 
B) lysosomal proteins 
C) proteins required to dock the vesicle to an acceptor membrane 
D) proteins required to target the vesicle to an acceptor membrane 
E) all of these components 
A) secretory proteins 
B) lysosomal proteins 
C) proteins required to dock the vesicle to an acceptor membrane 
D) proteins required to target the vesicle to an acceptor membrane 
E) all of these components

Question 10

You are working on a project in which you block autophagy in a particular portion of the brain of a laboratory animal. What happens to these animals? (Select all correct choices)

Accepted Answer

A) Nothing happens since nerve cells are so long-lived. 
B) That region of the nervous system experiences a massive loss of nerve cells. 
C) There is slight, but not dangerous damage, to the organelles and proteins of the nerve cells. 
D) There is continuous damage to the proteins and organelles of these long-lived cells. 
A) Nothing happens since nerve cells are so long-lived. 
B) That region of the nervous system experiences a massive loss of nerve cells. 
C) There is slight, but not dangerous damage, to the organelles and proteins of the nerve cells. 
D) There is continuous damage to the proteins and organelles of these long-lived cells.

Question 11

Synaptic vesicle fusion to the presynaptic membrane in a neuron is regulated by what calcium-binding protein found in the membrane of the synaptic vesicle?

Accepted Answer

A) synaptin 
B) synaptogenin 
C) calmodulin 
D) calcitonin 
E) synaptotagmin 
A) synaptin 
B) synaptogenin 
C) calmodulin 
D) calcitonin 
E) synaptotagmin

Question 12

CDG1b results from a deficiency in what enzyme?

Accepted Answer

A) phosphomannose phosphatase 
B) phosphotungstate isomerase 
C) phosphomannose isomerase 
D) phosphatase 
E) phosphoenol pyruvate carboxylase 
A) phosphomannose phosphatase 
B) phosphotungstate isomerase 
C) phosphomannose isomerase 
D) phosphatase 
E) phosphoenol pyruvate carboxylase

Question 13

What is the arrangement of organelles in a secretory cell from the basal end to the apical end, an arrangement that reflects the flow of secretory products from synthesis to discharge?

Accepted Answer

A) nucleus and RER - SER - Golgi complex - secretory vesicles 
B) Golgi complex - nucleus and RER - SER - secretory vesicles 
C) nucleus and RER - Golgi complex - SER - secretory vesicles 
D) SER - nucleus and RER - Golgi complex - secretory vesicles 
E) secretory vesicles - nucleus and RER - SER - Golgi complex 
A) nucleus and RER - SER - Golgi complex - secretory vesicles 
B) Golgi complex - nucleus and RER - SER - secretory vesicles 
C) nucleus and RER - Golgi complex - SER - secretory vesicles 
D) SER - nucleus and RER - Golgi complex - secretory vesicles 
E) secretory vesicles - nucleus and RER - SER - Golgi complex

Question 14

What is responsible for destroying misfolded proteins in the cytoplasm?

Accepted Answer

A) polysomes 
B) polyribosomes 
C) peroxisomes 
D) proteasomes 
E) spliceosome 
A) polysomes 
B) polyribosomes 
C) peroxisomes 
D) proteasomes 
E) spliceosome

Question 15

Which molecules do the AP2 adaptors of the clathrin coat connect?

Accepted Answer

A) GGA adaptors and clathrin molecules 
B) the cytoplasmic tails of specific membrane receptors and clathrin molecules 
C) the luminal tails of specific membrane receptors and clathrin molecules 
D) the clathrin molecules and cargo molecules 
E) cargo molecules and the cytoplasmic tails of specific membrane receptors 
A) GGA adaptors and clathrin molecules 
B) the cytoplasmic tails of specific membrane receptors and clathrin molecules 
C) the luminal tails of specific membrane receptors and clathrin molecules 
D) the clathrin molecules and cargo molecules 
E) cargo molecules and the cytoplasmic tails of specific membrane receptors

Question 16

Which techniques are currently used to harvest extracellular vesicles for use in drug delivery research? (Select all correct choices)

Accepted Answer

A) extraction by ultracentrifugation 
B) isolation through affinity purification techniques 
C) creation of mutant gene product vesicles with therapeutic proteins inside them 
D) overexpression of therapeutic RNAs in vesicle-producing cells 
A) extraction by ultracentrifugation 
B) isolation through affinity purification techniques 
C) creation of mutant gene product vesicles with therapeutic proteins inside them 
D) overexpression of therapeutic RNAs in vesicle-producing cells

Question 17

All of the following toxic substances may be stored in plant vacuoles EXCEPT:

Accepted Answer

A) strychnine 
B) glycosides containing cyanide 
C) digitalis 
D) glucosinolates containing cyanide 
A) strychnine 
B) glycosides containing cyanide 
C) digitalis 
D) glucosinolates containing cyanide

Question 18

How does UGGT recognize incompletely folded or misfolded proteins that have been recently synthesized?

Accepted Answer

A) Such proteins display exposed hydrophilic residues that are absent from properly folded proteins. 
B) Five histidine residues are exposed on the protein's surface when it is improperly folded. 
C) Such proteins display exposed hydrophobic residues that are absent from properly folded proteins. 
D) Six arginine residues are exposed on the protein's surface when it is improperly folded. 
E) Such proteins display numerous carboxyl groups on their surfaces, which decreases their solubility. 
A) Such proteins display exposed hydrophilic residues that are absent from properly folded proteins. 
B) Five histidine residues are exposed on the protein's surface when it is improperly folded. 
C) Such proteins display exposed hydrophobic residues that are absent from properly folded proteins. 
D) Six arginine residues are exposed on the protein's surface when it is improperly folded. 
E) Such proteins display numerous carboxyl groups on their surfaces, which decreases their solubility.

Question 19

What acts as an address directing lysosomal enzymes to lysosomes?

Accepted Answer

A) a lysosomal peptide 
B) mannose-6-sulfate residues on the enzyme 
C) mannose-6-phosphate residues on the enzyme 
D) a signal peptide on the enzyme 
E) a stroma transfer peptide on the enzyme 
A) a lysosomal peptide 
B) mannose-6-sulfate residues on the enzyme 
C) mannose-6-phosphate residues on the enzyme 
D) a signal peptide on the enzyme 
E) a stroma transfer peptide on the enzyme

Question 20

What are the recognition signals for lysosomal enzymes that allow them to be localized correctly in lysosomes?

Accepted Answer

A) Lysosomal enzymes possess sulfated mannose residues on N-linked carbohydrate chains. 
B) Lysosomal enzymes possess phosphorylated mannose residues on N-linked carbohydrate chains. 
C) Lysosomal enzymes possess phosphorylated mannose residues on O-linked carbohydrate chains. 
D) Lysosomal enzymes possess sulfated mannose residues on O-linked carbohydrate chains. 
E) Lysosomal enzymes possess phosphorylated glucose residues on N-linked carbohydrate chains. 
A) Lysosomal enzymes possess sulfated mannose residues on N-linked carbohydrate chains. 
B) Lysosomal enzymes possess phosphorylated mannose residues on N-linked carbohydrate chains. 
C) Lysosomal enzymes possess phosphorylated mannose residues on O-linked carbohydrate chains. 
D) Lysosomal enzymes possess sulfated mannose residues on O-linked carbohydrate chains. 
E) Lysosomal enzymes possess phosphorylated glucose residues on N-linked carbohydrate chains.

When electron micrographs were first taken of the cell interior, what kinds of structures were seen?

Why does the cell use proteasomes to destroy misfolded proteins?

Where is this common domain of SNAREs located, of what is it composed and what is it called?

What allows smooth and rough vesicles (microsomes)to be readily separated by density gradient centrifugation?

When Rabs have bound to GTP, what do they do?

What is thought to shield lysosomal membranes against attack by their enclosed enzymes?

What determines the sequence of sugar addition to glycoproteins traveling through the Golgi complex?

Which GTP-binding protein plays a regulatory role by initiating vesicle formation and by regulating the assembly of the vesicle's COPII coat?

Which components below are selected for transport by vesicles originating in the Golgi complex?

You are working on a project in which you block autophagy in a particular portion of the brain of a laboratory animal. What happens to these animals? (Select all correct choices)

Synaptic vesicle fusion to the presynaptic membrane in a neuron is regulated by what calcium-binding protein found in the membrane of the synaptic vesicle?

CDG1b results from a deficiency in what enzyme?

What is the arrangement of organelles in a secretory cell from the basal end to the apical end, an arrangement that reflects the flow of secretory products from synthesis to discharge?

What is responsible for destroying misfolded proteins in the cytoplasm?

Which molecules do the AP2 adaptors of the clathrin coat connect?

Which techniques are currently used to harvest extracellular vesicles for use in drug delivery research? (Select all correct choices)

All of the following toxic substances may be stored in plant vacuoles EXCEPT:

How does UGGT recognize incompletely folded or misfolded proteins that have been recently synthesized?

What acts as an address directing lysosomal enzymes to lysosomes?

What are the recognition signals for lysosomal enzymes that allow them to be localized correctly in lysosomes?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics, Enzymes and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

Exam 8: Cytoplasmic Membrane Systems: Structure, Function, and Membrane Trafficking

When electron micrographs were first taken of the cell interior, what kinds of structures were seen?

Why does the cell use proteasomes to destroy misfolded proteins?

Where is this common domain of SNAREs located, of what is it composed and what is it called?

What allows smooth and rough vesicles (microsomes)to be readily separated by density gradient centrifugation?

When Rabs have bound to GTP, what do they do?

What is thought to shield lysosomal membranes against attack by their enclosed enzymes?

What determines the sequence of sugar addition to glycoproteins traveling through the Golgi complex?

Which GTP-binding protein plays a regulatory role by initiating vesicle formation and by regulating the assembly of the vesicle's COPII coat?

Which components below are selected for transport by vesicles originating in the Golgi complex?

You are working on a project in which you block autophagy in a particular portion of the brain of a laboratory animal. What happens to these animals? (Select all correct choices)

Synaptic vesicle fusion to the presynaptic membrane in a neuron is regulated by what calcium-binding protein found in the membrane of the synaptic vesicle?

CDG1b results from a deficiency in what enzyme?

What is the arrangement of organelles in a secretory cell from the basal end to the apical end, an arrangement that reflects the flow of secretory products from synthesis to discharge?

What is responsible for destroying misfolded proteins in the cytoplasm?

Which molecules do the AP2 adaptors of the clathrin coat connect?

Which techniques are currently used to harvest extracellular vesicles for use in drug delivery research? (Select all correct choices)

All of the following toxic substances may be stored in plant vacuoles EXCEPT:

How does UGGT recognize incompletely folded or misfolded proteins that have been recently synthesized?

What acts as an address directing lysosomal enzymes to lysosomes?

What are the recognition signals for lysosomal enzymes that allow them to be localized correctly in lysosomes?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics, Enzymes and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters