Question 1

What are the two sites within a cell at which protein synthesisoccurs?

Accepted Answer

A) cytosolic surface of RER and cisternal surface of RER 
B) cytosolic surface of RER and free ribosomes 
C) cisternal surface of RER and free ribosomes 
D) free ribosomes and cytosolic surface of SER 
E) cytosolic surface of RER and cytosolic surface of SER 
A) cytosolic surface of RER and cisternal surface of RER 
B) cytosolic surface of RER and free ribosomes 
C) cisternal surface of RER and free ribosomes 
D) free ribosomes and cytosolic surface of SER 
E) cytosolic surface of RER and cytosolic surface of SER

Question 2

What drives the engulfment of particulate material by phagocytosis?

Accepted Answer

A) actin-containing microfilaments that underlie the plasma membrane 
B) tubulin-containing microtubules that underlie the plasma membrane 
C) actin-containing microfilaments that underlie the mitochondrial membrane 
D) myosin-containing microfilaments that underlie the plasma membrane 
E) tubulin-containing microtubules that underlie the mitochondrial membrane 
A) actin-containing microfilaments that underlie the plasma membrane 
B) tubulin-containing microtubules that underlie the plasma membrane 
C) actin-containing microfilaments that underlie the mitochondrial membrane 
D) myosin-containing microfilaments that underlie the plasma membrane 
E) tubulin-containing microtubules that underlie the mitochondrial membrane

Question 3

Which model of Golgi complex formation suggests that the cisternae of a Golgi stack remain in place as stable compartments held together by a protein scaffold, while the cargo is shuttled through the Golgi via vesicles that bud from one compartment and fuse with a neighboring one?

Accepted Answer

A) the cisternal maturation model 
B) the cargo carrying model 
C) the vesicular transport model 
D) the secretory transport model 
E) the chemiosmotic model 
A) the cisternal maturation model 
B) the cargo carrying model 
C) the vesicular transport model 
D) the secretory transport model 
E) the chemiosmotic model

Question 4

Sec23 and Sec24 bind together to form a "banana-shaped" dimer. What is the purpose of this dimer?

Accepted Answer

A) Because of its linear shape, it firms up the membrane. 
B) Because of its curved shape, the dimer puts pressure on the membrane surface to help it further bend into a curved bud. 
C) Because of its curved shape, the dimer puts pressure on the membrane surface to help it disintegrate. 
D) The dimer stabilizes the Golgi complex membrane. 
E) The dimer joins with other dimers to form a remarkably stable cage. 
A) Because of its linear shape, it firms up the membrane. 
B) Because of its curved shape, the dimer puts pressure on the membrane surface to help it further bend into a curved bud. 
C) Because of its curved shape, the dimer puts pressure on the membrane surface to help it disintegrate. 
D) The dimer stabilizes the Golgi complex membrane. 
E) The dimer joins with other dimers to form a remarkably stable cage.

Question 5

I-cell disease is typified by __________.

Accepted Answer

A) lysosomes bloated with undegraded materials 
B) the production of normal levels of lysosomal enzymes without the mannose 6-phosphate residues normally present 
C) lysosomal enzymes being secreted by the cell because they have not been targeted to lysosomes 
D) a deficiency in N-acetylglucosamine phosphotransferase 
E) all of these are correct 
A) lysosomes bloated with undegraded materials 
B) the production of normal levels of lysosomal enzymes without the mannose 6-phosphate residues normally present 
C) lysosomal enzymes being secreted by the cell because they have not been targeted to lysosomes 
D) a deficiency in N-acetylglucosamine phosphotransferase 
E) all of these are correct

Question 6

What leads to the degradation of the contents of late endosomes by lysosomal enzymes?

Accepted Answer

A) secretion of lysosomal enzymes into late endosomes 
B) transport of lysosomal enzymes into late endosomes through specialized pore complexes 
C) fusion of late endosomes containing intralumenal vesicles with a lysosome 
D) fusion of early endosomes with lysosomes; late endosomes lowering their internal pH activating the enzymes 
E) late endosomes synthesizing lysosomal enzymes that then degrade the contents 
A) secretion of lysosomal enzymes into late endosomes 
B) transport of lysosomal enzymes into late endosomes through specialized pore complexes 
C) fusion of late endosomes containing intralumenal vesicles with a lysosome 
D) fusion of early endosomes with lysosomes; late endosomes lowering their internal pH activating the enzymes 
E) late endosomes synthesizing lysosomal enzymes that then degrade the contents

Question 7

When cells are homogenized, the cytomembrane system is broken into fragments, which can fuse to form small membranous spheres called ________.

Accepted Answer

A) vacuoles 
B) victuals 
C) vesicles 
D) nuclei 
E) endosomes 
A) vacuoles 
B) victuals 
C) vesicles 
D) nuclei 
E) endosomes

Question 8

Which of the following organelles import(s)proteins through one or more outer boundary membranes?

Accepted Answer

A) the nucleus 
B) mitochondria 
C) chloroplasts 
D) peroxisomes 
E) all of these are correct 
A) the nucleus 
B) mitochondria 
C) chloroplasts 
D) peroxisomes 
E) all of these are correct

Question 9

Where are misfolded secretory proteins eventually destroyed?

Accepted Answer

A) in the RER 
B) in the SER 
C) in the Golgi complex 
D) in the cytosol (cytoplasm) 
E) in the nucleus 
A) in the RER 
B) in the SER 
C) in the Golgi complex 
D) in the cytosol (cytoplasm) 
E) in the nucleus

Question 10

Why are yeast cells often used to study eukaryotic gene mutations affecting secretion and other cytomembrane processes?

Accepted Answer

A) They have only a few genes. 
B) They are small and single-celled and can be cultured easily. 
C) They can be grown as haploid organisms so mutants are easily seen. 
D) Deficiencies in yeast cells caused by mutants are easily detected. 
E) All of these are correct. 
A) They have only a few genes. 
B) They are small and single-celled and can be cultured easily. 
C) They can be grown as haploid organisms so mutants are easily seen. 
D) Deficiencies in yeast cells caused by mutants are easily detected. 
E) All of these are correct.

Question 11

Once an organelle to be destroyed, like a mitochondrion, has been surrounded with a double membrane, what is the name of the structure that has been produced?

Accepted Answer

A) autophagolysosome 
B) phagolysosome 
C) bacteriophage 
D) phagosome 
E) autophagosome 
A) autophagolysosome 
B) phagolysosome 
C) bacteriophage 
D) phagosome 
E) autophagosome

Question 12

A cellular phenomenon called RNA interference (RNAi)is a process in which cells produce small RNAs called _________ bind to specific mRNAs and inhibit the translation of these mRNAs into proteins.

Accepted Answer

A) snRNAs 
B) isRNAs 
C) mRNAs 
D) RNAsi 
E) siRNAs 
A) snRNAs 
B) isRNAs 
C) mRNAs 
D) RNAsi 
E) siRNAs

Question 13

What is usually the retrieval signal for escaped ER membrane proteins?

Accepted Answer

A) KKXX at the C-terminus of the protein 
B) KDEL at the C-terminus of the protein 
C) KDEL at the N-terminus of the protein 
D) KKXX at the N-terminus of the protein 
E) KXEL at the C-terminus of the protein 
A) KKXX at the C-terminus of the protein 
B) KDEL at the C-terminus of the protein 
C) KDEL at the N-terminus of the protein 
D) KKXX at the N-terminus of the protein 
E) KXEL at the C-terminus of the protein

Question 14

Which of the following is a mitochondrial subcompartment into which proteins can be delivered?

Accepted Answer

A) outer mitochondrial membrane (OMM) 
B) inner mitochondrial membrane (IMM) 
C) intermembrane space 
D) matrix 
E) all of these are correct 
A) outer mitochondrial membrane (OMM) 
B) inner mitochondrial membrane (IMM) 
C) intermembrane space 
D) matrix 
E) all of these are correct

Question 15

What kind(s)of modifications are made in proteins as they move through the Golgi complex?

Accepted Answer

A) The protein's carbohydrates are modified by a series of stepwise enzymatic reactions. 
B) Amino acids can be added to either end of the polypeptide chain. 
C) Amino acids in the proteins may be chemically altered into nucleic acids. 
D) Small segments of amino acids can be added into the center of an existing protein. 
E) All of these are correct. 
A) The protein's carbohydrates are modified by a series of stepwise enzymatic reactions. 
B) Amino acids can be added to either end of the polypeptide chain. 
C) Amino acids in the proteins may be chemically altered into nucleic acids. 
D) Small segments of amino acids can be added into the center of an existing protein. 
E) All of these are correct.

Question 16

Which molecule type is thought to direct the movement of vesicles through the cytoplasm to their final destination?

Accepted Answer

A) microfilaments 
B) microtubules 
C) intermediate filaments 
D) collagen 
E) keratin 
A) microfilaments 
B) microtubules 
C) intermediate filaments 
D) collagen 
E) keratin

Question 17

Cells are infected with a virus carrying a temperature-sensitive mutant VSVG gene that encodes a protein that cannot leave the ER of infected cells grown at restrictive temperatures (40oC). Thus, at higher temperatures:

Accepted Answer

A) VSVG protein heads immediately for the Golgi complex. 
B) VSVG protein cannot leave the ER. 
C) VSVG protein leaves the ER immediately. 
D) all of the manufactured VSVG protein leaves the ER synchronously. 
E) VSVG protein is degraded rapidly and never passes to the Golgi complex. 
A) VSVG protein heads immediately for the Golgi complex. 
B) VSVG protein cannot leave the ER. 
C) VSVG protein leaves the ER immediately. 
D) all of the manufactured VSVG protein leaves the ER synchronously. 
E) VSVG protein is degraded rapidly and never passes to the Golgi complex.

Question 18

Where in the Golgi complex does most protein sorting occur?

Accepted Answer

A) the medial cisternae 
B) the TGN 
C) the CGN 
D) the cis network 
E) the pre-Golgi network 
A) the medial cisternae 
B) the TGN 
C) the CGN 
D) the cis network 
E) the pre-Golgi network

Question 19

When a mitochondrial chaperone helps a mitochondrial matrix protein into the matrix by biased diffusion, the chaperone is said to be acting as ______.

Accepted Answer

A) a Brownian motion 
B) a biased diffuser 
C) a Brownian ratchet 
D) a misratchet 
E) an unbiased diffuser 
A) a Brownian motion 
B) a biased diffuser 
C) a Brownian ratchet 
D) a misratchet 
E) an unbiased diffuser

Question 20

Which of the following strategies is used by Mycobacterium tuberculosis, the bacterium responsible for tuberculosis, to avoid being destroyed by phagocytosis?

Accepted Answer

A) The bacterium crystallizes the enzymes in the phagolysosome. 
B) The bacterium inhibits fusion of the phagosome with a lysosome. 
C) The bacterium allows fusion with the lysosome, but neither the acidic pH nor the lysosomal enzymes can destroy it. 
D) The bacterium produces proteins that destroy lysosomal membrane integrity so that the bacterium can escape into the cell cytosol. 
E) The bacterium neutralizes the enzymes in the lysosome. 
A) The bacterium crystallizes the enzymes in the phagolysosome. 
B) The bacterium inhibits fusion of the phagosome with a lysosome. 
C) The bacterium allows fusion with the lysosome, but neither the acidic pH nor the lysosomal enzymes can destroy it. 
D) The bacterium produces proteins that destroy lysosomal membrane integrity so that the bacterium can escape into the cell cytosol. 
E) The bacterium neutralizes the enzymes in the lysosome.

What are the two sites within a cell at which protein synthesisoccurs?

What drives the engulfment of particulate material by phagocytosis?

Which model of Golgi complex formation suggests that the cisternae of a Golgi stack remain in place as stable compartments held together by a protein scaffold, while the cargo is shuttled through the Golgi via vesicles that bud from one compartment and fuse with a neighboring one?

Sec23 and Sec24 bind together to form a "banana-shaped" dimer. What is the purpose of this dimer?

I-cell disease is typified by __________.

What leads to the degradation of the contents of late endosomes by lysosomal enzymes?

When cells are homogenized, the cytomembrane system is broken into fragments, which can fuse to form small membranous spheres called ________.

Which of the following organelles import(s)proteins through one or more outer boundary membranes?

Where are misfolded secretory proteins eventually destroyed?

Why are yeast cells often used to study eukaryotic gene mutations affecting secretion and other cytomembrane processes?

Once an organelle to be destroyed, like a mitochondrion, has been surrounded with a double membrane, what is the name of the structure that has been produced?

A cellular phenomenon called RNA interference (RNAi)is a process in which cells produce small RNAs called _________ bind to specific mRNAs and inhibit the translation of these mRNAs into proteins.

What is usually the retrieval signal for escaped ER membrane proteins?

Which of the following is a mitochondrial subcompartment into which proteins can be delivered?

What kind(s)of modifications are made in proteins as they move through the Golgi complex?

Which molecule type is thought to direct the movement of vesicles through the cytoplasm to their final destination?

Cells are infected with a virus carrying a temperature-sensitive mutant VSVG gene that encodes a protein that cannot leave the ER of infected cells grown at restrictive temperatures (40^oC). Thus, at higher temperatures:

Where in the Golgi complex does most protein sorting occur?

When a mitochondrial chaperone helps a mitochondrial matrix protein into the matrix by biased diffusion, the chaperone is said to be acting as ______.

Which of the following strategies is used by Mycobacterium tuberculosis, the bacterium responsible for tuberculosis, to avoid being destroyed by phagocytosis?

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

What are the two sites within a cell at which protein synthesisoccurs?

What drives the engulfment of particulate material by phagocytosis?

Which model of Golgi complex formation suggests that the cisternae of a Golgi stack remain in place as stable compartments held together by a protein scaffold, while the cargo is shuttled through the Golgi via vesicles that bud from one compartment and fuse with a neighboring one?

Sec23 and Sec24 bind together to form a "banana-shaped" dimer. What is the purpose of this dimer?

I-cell disease is typified by __________.

What leads to the degradation of the contents of late endosomes by lysosomal enzymes?

When cells are homogenized, the cytomembrane system is broken into fragments, which can fuse to form small membranous spheres called ________.

Which of the following organelles import(s)proteins through one or more outer boundary membranes?

Where are misfolded secretory proteins eventually destroyed?

Why are yeast cells often used to study eukaryotic gene mutations affecting secretion and other cytomembrane processes?

Once an organelle to be destroyed, like a mitochondrion, has been surrounded with a double membrane, what is the name of the structure that has been produced?

A cellular phenomenon called RNA interference (RNAi)is a process in which cells produce small RNAs called _________ bind to specific mRNAs and inhibit the translation of these mRNAs into proteins.

What is usually the retrieval signal for escaped ER membrane proteins?

Which of the following is a mitochondrial subcompartment into which proteins can be delivered?

What kind(s)of modifications are made in proteins as they move through the Golgi complex?

Which molecule type is thought to direct the movement of vesicles through the cytoplasm to their final destination?

Cells are infected with a virus carrying a temperature-sensitive mutant VSVG gene that encodes a protein that cannot leave the ER of infected cells grown at restrictive temperatures (40oC). Thus, at higher temperatures:

Where in the Golgi complex does most protein sorting occur?

When a mitochondrial chaperone helps a mitochondrial matrix protein into the matrix by biased diffusion, the chaperone is said to be acting as ______.

Which of the following strategies is used by Mycobacterium tuberculosis, the bacterium responsible for tuberculosis, to avoid being destroyed by phagocytosis?

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

Cells are infected with a virus carrying a temperature-sensitive mutant VSVG gene that encodes a protein that cannot leave the ER of infected cells grown at restrictive temperatures (40^oC). Thus, at higher temperatures: