Question 1

Which of the following organelles imports proteins in their native,folded conformation?

Accepted Answer

A) mitochondria 
B) chloroplasts 
C) peroxisomes 
D) nuclei 
E) lysosomes 
A) mitochondria 
B) chloroplasts 
C) peroxisomes 
D) nuclei 
E) lysosomes

Question 2

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 sugars 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 sugars in the Golgi complex. 
E) the sequence of nucleotides in the Golgi complex

Question 3

How are signaling receptors typically marked for endocytosis and subsequent destruction? What evidence demonstrates ubiquitin's role in the internalization of membrane proteins?

Accepted Answer

Signaling receptors are typically marked

Question 4

What 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 5

About what time does PI(4,5)P2 disappear from a site of endocytosis?

Accepted Answer

A) about the time the coated pit forms 
B) about the time the coated vesicle is pinched away from the plasma membrane 
C) when the ligand binds to the receptors 
D) well after the vesicle has pinched away from the plasma membrane 
E) as the coated pit rounds into a larger coated pit 
A) about the time the coated pit forms 
B) about the time the coated vesicle is pinched away from the plasma membrane 
C) when the ligand binds to the receptors 
D) well after the vesicle has pinched away from the plasma membrane 
E) as the coated pit rounds into a larger coated pit

Question 6

Many of the proteins that reside within the thylakoid membrane are encoded by chloroplast genes and synthesized on __________.

Accepted Answer

A) ribosomes floating in the stroma 
B) ribosomes bound to the outer surface of the thylakoid membrane 
C) ribosomes bound to the inner chloroplast membrane 
D) ribosomes inside the thylakoid disks 
E) cytoplasmic ribosomes 
A) ribosomes floating in the stroma 
B) ribosomes bound to the outer surface of the thylakoid membrane 
C) ribosomes bound to the inner chloroplast membrane 
D) ribosomes inside the thylakoid disks 
E) cytoplasmic ribosomes

Question 7

The phosphorylated rings of phosphoinositides are recognized and bound by particular proteins.Where are the phosphorylated rings located?

Accepted Answer

A) They reside in the membrane interior. 
B) They are found in lysosomes. 
C) They reside at the membrane surface. 
D) They reside inside the clathrin coat. 
E) They reside inside the COPII-coat. 
A) They reside in the membrane interior. 
B) They are found in lysosomes. 
C) They reside at the membrane surface. 
D) They reside inside the clathrin coat. 
E) They reside inside the COPII-coat.

Question 8

What mediates the interaction between integral membrane proteins to be transported in COPII-coated vesicles and the COPII-coat?

Accepted Answer

A) ER export signals in the luminal tails of integral ER membrane proteins 
B) ER export signals in the cytosolic tails of integral ER membrane proteins 
C) ER export signals in ER phospholipids that interact with the membrane proteins 
D) ER export signals in carbohydrates on the cytosolic tails of integral ER membrane proteins 
E) ER export signals in carbohydrates on the luminal tails of integral ER membrane proteins 
A) ER export signals in the luminal tails of integral ER membrane proteins 
B) ER export signals in the cytosolic tails of integral ER membrane proteins 
C) ER export signals in ER phospholipids that interact with the membrane proteins 
D) ER export signals in carbohydrates on the cytosolic tails of integral ER membrane proteins 
E) ER export signals in carbohydrates on the luminal tails of integral ER membrane proteins

Question 9

How do Rabs appear to associate with membranes?

Accepted Answer

A) via microtubules 
B) via a lipid anchor 
C) via intermediate filaments 
D) via vimentin filaments 
E) via filaments 
A) via microtubules 
B) via a lipid anchor 
C) via intermediate filaments 
D) via vimentin filaments 
E) via filaments

Question 10

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 11

What happens to the breakdown products of materials brought into many single-celled organisms from the extracellular environment?

Accepted Answer

A) They are used as nutrients and are released to the extracellular space. 
B) They are used as nutrients and are released into the cytoplasm. 
C) Peptides produced during digestion are posted on the cell surface. 
D) They are used to build the nuclear envelope and are released into the cytoplasm. 
E) They are maintained within the lysosome and used for building new lysosomes. 
A) They are used as nutrients and are released to the extracellular space. 
B) They are used as nutrients and are released into the cytoplasm. 
C) Peptides produced during digestion are posted on the cell surface. 
D) They are used to build the nuclear envelope and are released into the cytoplasm. 
E) They are maintained within the lysosome and used for building new lysosomes.

Question 12

What happens to the clathrin coat once the vesicle has budded from the Golgi body?

Accepted Answer

A) It is lost. 
B) It is strengthened. 
C) It is rearranged. 
D) It is thickened. 
E) It swells. 
A) It is lost. 
B) It is strengthened. 
C) It is rearranged. 
D) It is thickened. 
E) It swells.

Question 13

Where does the PTS receptor bind to peroxisome-destined proteins?

Accepted Answer

A) in the nucleus 
B) in the cytoplasm (cytosol) 
C) in the mitochondrion 
D) in the peroxisome 
E) in the RER 
A) in the nucleus 
B) in the cytoplasm (cytosol) 
C) in the mitochondrion 
D) in the peroxisome 
E) in the RER

Question 14

What information does the use of siRNAs provide?

Accepted Answer

They can be used to determine and identi

Question 15

The ER reportedly contains sensors that monitor the concentration of unfolded or misfolded proteins in the lumen.One proposal suggests that the sensors are normally kept in an inactive state by ______,particularly ______.

Accepted Answer

A) molecular chaperones,ribosomes 
B) proteasomes,BiP 
C) molecular chaperones,BiP 
D) enzymes,ER 
E) molecular chaperones,Rubisco 
A) molecular chaperones,ribosomes 
B) proteasomes,BiP 
C) molecular chaperones,BiP 
D) enzymes,ER 
E) molecular chaperones,Rubisco

Question 16

Which of the following strategies is used by Listeria monocytogenes,a bacterium that causes meningitis,to avoid being destroyed by a lysosome's fusion with the phagosome in which it was ingested?

Accepted Answer

A) The bacterium allows fusion with the lysosome,but the acidic pH cannot destroy it. 
B) The bacterium inhibits fusion of the phagosome with a lysosome. 
C) The bacterium allows fusion with the lysosome,but the lysosomal enzymes cannot 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 allows fusion with the lysosome,but the acidic pH cannot destroy it. 
B) The bacterium inhibits fusion of the phagosome with a lysosome. 
C) The bacterium allows fusion with the lysosome,but the lysosomal enzymes cannot 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.

Question 17

What is responsible for adding sugars to dolichol phosphate?

Accepted Answer

A) membrane-bound glycosyltransferases 
B) membrane-bound oligosaccharyltransferase 
C) membrane-bound gangliosidase 
D) glycosylsynthetase 
E) peptidyltransferase 
A) membrane-bound glycosyltransferases 
B) membrane-bound oligosaccharyltransferase 
C) membrane-bound gangliosidase 
D) glycosylsynthetase 
E) peptidyltransferase

Question 18

What would happen if the enzyme that adds phosphate groups to the appropriate mannose residues on the carbohydrate chains of lysosomal enzymes were defective?

Accepted Answer

A) Lysosomal enzymes would be localized to lysosomes. 
B) Lysosomal enzymes would be localized to peroxisomes. 
C) Lysosomal enzymes would continue through the Golgi complex to secretory vesicles and would eventually be secreted. 
D) Lysosomal enzymes would be degraded. 
E) Lysosomal enzymes would be degraded 
A) Lysosomal enzymes would be localized to lysosomes. 
B) Lysosomal enzymes would be localized to peroxisomes. 
C) Lysosomal enzymes would continue through the Golgi complex to secretory vesicles and would eventually be secreted. 
D) Lysosomal enzymes would be degraded. 
E) Lysosomal enzymes would be degraded

Question 19

What 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 20

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.

Which of the following organelles imports proteins in their native,folded conformation?

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

How are signaling receptors typically marked for endocytosis and subsequent destruction? What evidence demonstrates ubiquitin's role in the internalization of membrane proteins?

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

About what time does PI(4,5)P₂ disappear from a site of endocytosis?

Many of the proteins that reside within the thylakoid membrane are encoded by chloroplast genes and synthesized on __________.

The phosphorylated rings of phosphoinositides are recognized and bound by particular proteins.Where are the phosphorylated rings located?

What mediates the interaction between integral membrane proteins to be transported in COPII-coated vesicles and the COPII-coat?

How do Rabs appear to associate with membranes?

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

What happens to the breakdown products of materials brought into many single-celled organisms from the extracellular environment?

What happens to the clathrin coat once the vesicle has budded from the Golgi body?

Where does the PTS receptor bind to peroxisome-destined proteins?

What information does the use of siRNAs provide?

The ER reportedly contains sensors that monitor the concentration of unfolded or misfolded proteins in the lumen.One proposal suggests that the sensors are normally kept in an inactive state by ,particularly .

Which of the following strategies is used by Listeria monocytogenes,a bacterium that causes meningitis,to avoid being destroyed by a lysosome's fusion with the phagosome in which it was ingested?

What is responsible for adding sugars to dolichol phosphate?

What would happen if the enzyme that adds phosphate groups to the appropriate mannose residues on the carbohydrate chains of lysosomal enzymes were defective?

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

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

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

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

Which of the following organelles imports proteins in their native,folded conformation?

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

How are signaling receptors typically marked for endocytosis and subsequent destruction? What evidence demonstrates ubiquitin's role in the internalization of membrane proteins?

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

About what time does PI(4,5)P2 disappear from a site of endocytosis?

Many of the proteins that reside within the thylakoid membrane are encoded by chloroplast genes and synthesized on __________.

The phosphorylated rings of phosphoinositides are recognized and bound by particular proteins.Where are the phosphorylated rings located?

What mediates the interaction between integral membrane proteins to be transported in COPII-coated vesicles and the COPII-coat?

How do Rabs appear to associate with membranes?

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

What happens to the breakdown products of materials brought into many single-celled organisms from the extracellular environment?

What happens to the clathrin coat once the vesicle has budded from the Golgi body?

Where does the PTS receptor bind to peroxisome-destined proteins?

What information does the use of siRNAs provide?

The ER reportedly contains sensors that monitor the concentration of unfolded or misfolded proteins in the lumen.One proposal suggests that the sensors are normally kept in an inactive state by ______,particularly ______.

Which of the following strategies is used by Listeria monocytogenes,a bacterium that causes meningitis,to avoid being destroyed by a lysosome's fusion with the phagosome in which it was ingested?

What is responsible for adding sugars to dolichol phosphate?

What would happen if the enzyme that adds phosphate groups to the appropriate mannose residues on the carbohydrate chains of lysosomal enzymes were defective?

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

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

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

About what time does PI(4,5)P₂ disappear from a site of endocytosis?

The ER reportedly contains sensors that monitor the concentration of unfolded or misfolded proteins in the lumen.One proposal suggests that the sensors are normally kept in an inactive state by ,particularly .