Exam 3 Questions Flashcards
The fluid substance in the nucleus in which solutes are dissolved is called ___.
nucleoplasm
The protein containing fibrillar network in the nucleus is called ____.
nuclear matrix
An intermembrane space is found in the ______.
nuclear envelope
Which of the following will have the highest amount of DNA?
chromatin
The basic unit of inheritance called the “gene” resides in the _____.
chromatin
Which of the following promotes conversion of Ran-GTP to Ran-GDP?
RanGAP1
Ribosomes are made in the _____.
nucleolus
The nuclear pore complex is found in the _____.
nuclear envelope
The nuclear lamina provides mechanical support to the _____.
nuclear envelope
Which of the following will have the highest amount of lipids?
nuclear envelope
Which of the following will have the highest amount of proteins?
nuclear matrix
Which of the following stays in the cytoplasm?
RanGAP1
The nucleoprotein fibers that constitute the chromosomes are called ____.
chromatin
Nucleosomes are part of ______.
chromatin
The shape of the nucleus is maintained by the ____.
nuclear matrix
Which of the following will have the highest amount of RNA?
nucleoli
Which of the following will have the highest amount of carbohydrates?
nucleoplasm
Which of the following promotes conversion of Ran-GDP to Ran-GTP?
RCC1
Which of the following stays in the nucleus?
RCC1
Centromere is an example of ____.
Constitutive Heterochromatin
Transcription occurs in _____.
Euchromatin
Histones bind to _____.
All of the above
DNA polymerase binds to _____.
All of the above
The distal ends of the Y chromosome is an example of _______.
Constitutive Heterochromatin
Which of the following are basic proteins that associate with DNA?
Histones
Which of the following are involved in transcriptional regulation of gene expression?
Histones
Telomerase is an example of _____.
None of the above
A dispersed form of chromatin is known as _____.
Euchromatin
Methylated DNA is usually found in ______.
Facultative Heterochromatin
The inactive X chromosome is an example of _______.
Facultative Heterochromatin
Marked indentations on mitotic chromosomes are known as ____.
Centromeres
Which of the following are enzymes?
Telomerases
Which of the following prevent ends of chromosomes from fusing with one another?
Telomeres
The Barr body is an example of _____.
Facultative Heterochromatin
Telomere is an example of _____.
Constitutive Heterochromatin
Satellite DNA is usually found in ______.
Constitutive Heterochromatin
RNA polymerase binds to _____.
Euchromatin
The active parts of an X chromosome is an example of _______.
Euchromatin
Unusual stretches of repeated sequences which form caps at the ends of chromosomes are known as ____.
Telomeres
Which of the following is a reverse transcriptase that synthesizes DNA using RNA as template?
Telomerases
In the lac operon, the ligand is made by enzymes encoded by the_____.
none of the above
In the trp operon, the ligand-repressor protein complex binds to _____.
operator region
What happens if the operator region is removed from the lac operon?
the structural genes would always be expressed
What happens if the promoter region is removed from the trp operon?
the structural genes would never be expressed
What happens if the lac promoter and operator regions are replaced with those of the trp operon?
the structural genes would only be expressed in the absence of trp
What happens if the cAMP-CRP binding site is removed from the lac operon?
the structural genes would never be expressed
Which of the following happens in a repressible operon?
a and b (no)
In the absence of the ligand, the regulator does not bind to the operator.
The ligand-regulator complex does not bind to the operator.
c (no)
The ligand-regulator complex does not bind to the operator
b and c (no)
Which of the following occurs in the presence of tryptophan?
The ligand-regulator complex binds to the operator (no)
The ligand-regulator complex does not bind to the operator (no)
In which case will structural genes be expressed in an inducible operon?
The ligand-regulator complex does not bind to the operator.
What happens in when tryptophan is present?
The ligand-regulator complex binds to the operator
In the lac operon, to what does an inducer bind?
repressor protein
In the lac operon, the ligand-repressor protein complex binds to _____.
operator region (no)
none of the above
If there were a mutation in the regulatory gene of an inducible promoter rendering the protein incapable of binding to the inducer, then ______
the structural genes would never be expressed
What happens if the promoter region is removed from the lac operon?
the structural genes would never be expressed.
If there were a mutation in the regulatory gene of an inducible promoter rendering the protein incapable of binding to the corepressor, then ______
the structural genes would always be expressed
What happens if the trp promoter and operator regions are replaced with those of the lac operon?
the structural genes would only be expressed in the presence of lactose
Which of the following happens in an inducible operon?
a and c
Which of the following occurs in the presence of lactose?
a and c
In which case will transcription NOT occur in a repressible operon?
The regulator without the ligand binds to the operator (no)
The ligand-regulator complex binds to the operator.
What happens in when tryptophan is absent?
The regulator without the ligand does not bind to the operator
In the lac operon, what encodes the repressor protein?
regulatory gene
In the trp operon, the repressor protein without the ligand binds to _____.
none of the above
In the lac operon, the repressor protein without the ligand binds to _____.
operator region
What happens if the structural genes in a trp operon are mutated so that the encoded enzymes become nonfunctional?
the structural genes would only be expressed in the absence of the repressor
What happens if the regulatory gene in a lac operon is removed?
the structural genes would always be expressed
Which of the following is true for both inducible and repressible operons?
The ligand binds to the regulator protein.
Which of the following happens in an inducible operon?
b and c (no)
b (no)
The ligand-regulator complex binds to the operator.
Which of the following occurs in the trp operon?
a and b
The ligand binds to the regulator protein.
The ligand-regulator complex binds to the operator.
In which case will structural genes be expressed in a repressible operon?
The regulator without the ligand does not bind to the operator
What happens in the presence of lactose?
The ligand-regulator complex does not bind to the operator.
In the trp operon, to what does RNA polymerase bind?
promoter region
In the trp operon, the ligand is made by enzymes encoded by the_____.
structural genes
What happens if the operator region is removed from the trp operon?
the structural genes would always be expressed.
What happens if the structural genes in a lac operon are mutated so that the encoded enzymes become nonfunctional?
the structural genes would only be expressed in the presence of the inducer
What happens if the regulatory gene in a trp operon is removed?
the structural genes would always be expressed.
Which of the following is a difference between inducible versus repressible operons?
b and c
The ligand-regulator complex binds to the operator.
In the absence of the ligand, the regulator binds to the operator.
Which of the following occurs in the lac operon?
a and c
The ligand binds to the regulator protein.
In the absence of the ligand, the regulator binds to the operator.
In which case will transcription NOT occur in an inducible operon?
The regulator without the ligand does not bind to the operator (no)
The regulator without the ligand binds to the operator.
What happens in the absence of lactose?
The regulator without the ligand binds to the operator
If there were a mutation in the regulatory gene of a repressible promoter rendering the protein incapable of binding to the corepressor, then ______
the structural genes would always be expressed.
Which of the following is involved in genomic imprinting?
DNA methylation
The information that governs the cytoplasmic localization of an mRNA resides in the _____.
3’-UTR
Which of the following is involved in transcriptional activation?
histone acetylation
Which part of the mRNA protects it from being degraded by the exosome?
polyA tail
Iron regulatory protein binds to which region of the ferritin mRNA?
5’-UTR
The TATA box is a/an ______.
core promoter element
Which of the following is not a transcription factor motif?
TATA box
Which of the following disrupts histone-DNA interactions, which can lead to changes in the conformation of nucleosomes?
chromatin remodelling complex
Which of the following is a sequence-specific transcription factor?
glucocorticoid receptor
Which of the following is a general transcription factor?
TATA-binding protein (TBP)
The glucocorticoid response element is an example of a/an ______.
distal promoter element
Which of the following is a transcription factor motif present in the MYC gene, which is involved in the development of certain types of cancers?
helix-loop-helix
Which of the following has acetyltransferase activity?
histone modification complex
Which part of the mRNA is flanked by start and stop codons?
coding region
Which of the following is a transcription factor motif composed of three alpha helices organized into a boomerang shape?
HMG-box
Which of the following is involved in heterochromatin formation?
histone methylation
Which of the following is a transcription factor motif found in AP-1 (also known as Fos/Jun)?
leucine zipper
Which of the following binds to proteins of the nuclear matrix?
insulators
Which of the following is performed by subunits of large complexes called corepressors?
histone deacetylation
The CAAT box and the GC box are both ______.
proximal promoter elements
Which of the following is a transcription factor motif found in the glucocorticoid receptor?
zinc finger
DNA sequences that stimulate the transcription of a gene thousands of base pairs away are called ______.
enhancers
To initiate translation, the 40S ribosomal subunit binds to which part of the mRNA?
5’-UTR
Which of the following is involved in transcriptional repression of euchromatin?
histone deacetylation and histone methylation
Which of the following is a coactivator that interacts directly with RNA polymerase II?
Mediator
Telomerases are is involved in ____.
none of the above
Chromatin remodelling complex is involved in ____.
transcriptional level control of gene expression
Decapping enzyme is involved in ______.
translational level control of gene expression
Which of the following is involved in control of gene expression at the transcriptional level?
histone modification
The glucocorticoid receptor element is involved in ____.
transcriptional level control of gene expression
The CAAT box and the GC box are both involved in ________.
transcriptional level control of gene expression
Maskin is involved in ____.
translational level control of gene expression
The zip codes found in mRNA are involved in _____.
mRNA localization
U1 snRNPs are involved in _______.
processing level control of gene expression
Exonic splicing suppressors are involved in ________.
processing level control of gene expression
Which of the following is involved in control of gene expression at the post-translational level?
polyubiquitination
RanGAP1 is involved in ____.
none of the above
FOS and JUN are involved in ____.
transcriptional level control of gene expression
Ubiquitin ligase is involved in ____.
post-translational level control of gene expression
Which of the following is involved in control of gene expression at the mRNA processing level?
alternative splicing
Proteosomes are involved in ____.
post-translational level control of gene expression
Histone methyltransferases are involved in _______.
transcriptional level control of gene expression
The polyA nucleases are involved in ____.
translational level control of gene expression
Which of the following is involved in control of gene expression at the translational level?
mRNA localization
PolyA binding protein is involved in ______.
translational level control of gene expression
Which of the following cell fusion experiments can lead to premature compaction of duplicated interphase chromosomes, which appear pulverized under the microscope?
G1 + M (n)
G2 + M (n)
S + M?
Which of the following arrests the cell cycle upon UV irradiation?
phosphorylation of cdc25 by chk1
Which of the following is a cyclin dependent kinase inhibitor?
p21
Which of the following arrests the cell cycle at the G1 stage?
phosphorylation of p53 by chk2
Which of the following activates Cdks?
phosphorylation of cdc2 by CAK
Which of the following is required for G2 cells to enter mitosis?
phosphorylation of cdc2 by CAK
Which of the following cell fusion experiments can lead to premature compaction of duplicated interphase chromosomes, which remain intact and visible under the microscope?
G2 + S (n)
S + M (n)
G2 + M?
In which phase of the cell cycle are chromosomes duplicated?
S
Which of the following phosphorylates cdc25?
chk1
Which of the following leads to transcription of the p21 gene?
phosphorylation of p53 by chk2
Which of the following cell fusion experiments can lead to duplication of interphase chromosomes?
G1 + M (n)
G1 + S
In which phase of the cell cycle does the cell cyle stop upon DNA damage due to UV radiation?
G1 (no)
G2
Which of the following inactivates Cdks?
association with p21
Which of the following is a cyclin dependent kinase?
cdc2
Which of the following drives the cells into mitosis after the MPF is phosphorylated?
dephosphorylation of cdk by cdc25
Which of the following is a kinase?
cdc25 (no)
chk1
In which phase of the cell cycle are organelles duplicated?
G1
Which of the following cell fusion experiments can lead to premature compaction of unduplicated interphase chromosomes, which remain intact and visible under the microscope?
G2 + S (n)
S + M (n)
G1 + M?
In which phase of the cell cycle do mitotic cyclins accumulate?
G2
Which of the following activates Cdks?
a, b and c
A) association with a cyclin
B) phosphorylation at a critical tyrosine residue
C) association with p21
Which of the following is a transcription factor?
p53
Which of the following prevents G2 cells from entering mitosis?
phosphorylation of cdc2 by Wee1
In which phase of the cell cycle does the cell cyle stop upon DNA damage due to ionizing radiation?
G1
In which stage of mitosis do chromosomes move towards the spindle equator?
metaphase (n)
prometaphase
In which stage of mitosis do chromosomes align at the spindle equator?
metaphase
In which stage of mitosis do chromosomes move to opposite spindle poles?
anaphase
In which stage of mitosis does the nuclear envelope disperses?
prophase
Which of the following is in the correct order?
G1, G2, S, M (n)
M, G1, S, G2
In which stage of mitosis does the nuclear envelope assembles around chromosomes?
telophase
Which of the following is degraded by APCCdc20?
securin
Which of the following is degraded by APC?
b and c
Which of the following activates Cdks?
a and c
Which of the following move chromosomes to the poles?
Kinetochore microtubules
Which of the following is an adaptor protein that determines the substrate selection of the anaphase promoting complex?
cdc20
Which of the following guides the formation of a new cell wall in plants during cytokinesis?
phragmoplast
Which of the following is/are attached to chromosomes?
Kinetochore microtubules
Which of the following is the substrate of an active protease called separase?
cohesin
Which of the following is/are most directly involved in anaphase A?
Kinetochore microtubules
The movement of spindle poles away from each other is referred to as ______.
anaphase b
Which of the following is/are formed during telophase?
Contractile ring
Which of the following keep/s the spindle poles apart?
Polar spindle microtubules
Which of the following is/are the first to form during mitosis in animal cells?
Astral spindle fibers
Which of the following is/are made up of actin and myosin filaments?
Contractile ring
In plant cells, the formation of a new cell wall between two daughter cells begins with the construction of a _____.
cell plate
The plane of alignment of chromosomes during mitosis is called _____.
metaphase plate
Which of the following is a direct target of a checkpoint kinase?
cdc25
In which phase of the cell cycle are centrosomes duplicated?
S
Which of the following is/are the last to form during mitosis in animal cells?
Contractile ring
The cytoplasmic bridge between two daughter cells formed from remnants of the middle portion of the mitotic spindle is called _____.
midbody
Which of the following help/s determine the plane of cytokinesis in animal cells?
Astral spindle fibers
Which of the following is/are most directly involved in anaphase B?
Polar spindle microtubules
Which of the following is a direct target of cyclin dependent kinase?
condensin
Which of the following is degraded by SCF?
G1 cyclins
Which of the following is a direct target of a cdk-activating kinase?
cdc2
Which of the following help/s determine the plane of cytokinesis in plant cells?
Preprophase band
Which of the following is degraded by APCCdh-1?
mitotic cyclins
Which of the following can cause the separation of sister chromatids?
cdc20
Which of the following is/are formed during interphase?
Preprophase band
The movement of chromosomes toward the poles is referred to as ____.
anaphase a
Which of the following holds sister chromatids together?
cohesin
Which of the following uses cyclin dependent kinase as a substrate?
cdc25
Which of the following help/s position the spindle apparatus during metaphase?
Astral spindle fibers
Which of the following is a multiprotein complex involved in chromosome compaction?
condensin
What stage in cell division is characterized by the compaction of a diploid number of paired chromosomes and the disappearance of the nuclear membrane and the nucleolus, while the centrioles move toward opposite poles and the spindle forms?
prophase of meiosis I
In female gametogenesis, secondary oocytes stop at _____ before they are fertilized by a sperm.
metaphase II
Which of the following is a ladder like structure with transverse protein filaments connecting two lateral elements, which hold two homologous chromosomes together?
synaptonemal complex
At what stage of prophase I do chromosomes become visible?
Leptotene
At what stage of prophase I do synaptonemal complexes disappear?
Diplotene
What stage of cell division is characterized by the dispersion of a haploid number of chromosomes and the partial or complete reformation of the nuclear envelopes in the two daughter cells?
telophase of meiosis I and II (n)
telophase of mitosis (n)
telophase of mitosis I and meiosis II (n)
At what stage of prophase I is the meiotic spindle assembled?
Diakinesis
At what stage of prophase I are synaptonemal complexes fully formed?
Pachytene
What stage in cell division is characterized by the alignment of a diploid number of paired chromosomes at the center of the cell and the attachment of each homologue to chromosomal spindle fibers from opposite spindle poles?
metaphase of meiosis I
What stage in cell division is characterized by the compaction of a diploid number of unpaired chromosomes and the disappearance of the nuclear membrane and the nucleolus, while the centrioles move toward opposite poles and the spindle forms?
prophase of mitosis
In female gametogenesis, primary oocytes stop at _____ before they becomes secondary oocytes at puberty.
prophase I
In which stage of meiosis do homologous chromosomes separate?
anaphase I
In gametogenesis, the stage between primary spermatocytes and secondary spematocytes is _____.
interkinesis
At what stage of prophase I does synapsis begin?
Zygotene (n)
Pachytene (n)
Leptotene
Which of the following are 100-nm electron dense bodies which correspond to sites where crossing-over takes place?
recombination nodules
In which stage of meiosis do sister chromatids separate?
anaphase II
Which stage of meiosis ends the process of meiosis with chromosomes again enclosed by a nuclear envelope? The cells at this stage have a haploid amount of nuclear DNA and a haploid number of chromosomes.
telophase II
During which phase of meiosis do the kinetochores of sister chromatids face opposite poles as they line up in the center of the cells? The centromeres of sister chromatids become attached to chromosomal spindle fibers from opposite spindle poles.
metaphase II
What stage of cell division is characterized by the splitting of the centromeres of a diploid number of chromosomes and the movement of the resultant chromosomes toward opposite poles of the two daughter cells?
anaphase of mitosis and meiosis I (n)
anaphase of meiosis I (n)
What stage of cell division is characterized by the random splitting of the centromeres of a haploid number of unpaired chromosomes and their movement to opposite poles of the cell?
anaphase of meiosis II
At what stage of prophase I do synaptonemal complexes become visible?
Pachytene (n)
Zygotene
What stage in cell division is characterized by the alignment of a diploid number of unpaired chromosomes at the center of the cell and the attachment the kinetochore of each sister chromatid to chromosomal spindle fibers from opposite spindle poles?
metaphase of mitosis
Which stage of meiosis begins with the synchronous splitting of the centromeres, which hold the sister chromatids together, allowing the chromosomes to move toward opposite poles of the cell?
anaphase II
During which stage of meiosis have the chromosomes become recompacted after interkinesis? They begin to line up at the metaphase plate and if the nuclear envelope had reformed earlier, it is once again broken down.
prophase II
What stage of cell division is characterized by the dispersion of a diploid number of chromosomes and the reformation of the nuclear envelopes and nucleoli in two daughter cells?
telophase of meiosis I and II (n)
telophase of mitosis and meiosis I (n)
telophase of mitosis
What stage in cell division is characterized by the compaction of a haploid number of chromosomes and the disappearance of the nuclear membrane if it had reformed, while the centrioles move toward opposite poles and the spindle forms?
prophase of meiosis II
What stage in cell division is characterized by the alignment of a haploid number of chromosomes at the center of the cell and the attachment of the kinetochore of each sister chromatid to chromosomal spindle fibers from opposite spindle poles?
metaphase of meiosis II
What stage of cell division is characterized by the random separation of the maternal and paternal members of the homologous pairs and the movement of a haploid number of chromosome possessing two chromatids each to opposite poles of the cell?
anaphase of meiosis I
Which of the following refer to specific points of covalent attachments between homologous chromosomes?
chiasmata
What stage of cell division is characterized by the dispersion of a haploid number of chromosomes and the reformation of the nuclear envelopes in the four daughter cells?
telophase of meiosis II
What stage in cell division is characterized by the alignment of a diploid number of chromosomes at the center of the cell and the attachment of those chromosomes to the spindle?
metaphase of mitosis and meiosis I
Which of the following is activated by fertilization of the oocyte?
anaphase promoting complex
What stage in cell division is characterized by the compaction of chromosomes and the disappearance of the nuclear membrane and the nucleolus, while the centrioles move toward opposite poles and the spindle forms?
prophase of mitosis and prophase of meiosis I
Which of the following inactivates Cdks?
phosphorylation at a critical tyrosine residue
