Test 4 Flashcards

(107 cards)

1
Q

The process by which a cell in culture acquires the ability to divide indefinitely, similar to the division of cancer cells.

A

Transformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

A virus that infects bacteria; also called a phage.

A

Bacteriophages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

An infectious particle incapable of replicating outside of a cell, consisting of an RNA or DNA genome surrounded by a protein coat (capsid) and, for some viruses, a membranous envelope.

A

Virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The form of native DNA, referring to its two adjacent antiparallel polynucleotide strands wound around an imaginary axis into a spiral shape.

A

Double helix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Referring to the arrangement of the sugar-phosphate backbones in a DNA double helix

A

Antiparallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Type of DNA replication in which the replicated double helix consists of one old strand, derived from the parental molecule, and one newly made strand.

A

Semiconservative model

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Site where the replication of a DNA molecule begins, consisting of a specific sequence of nucleotides.

A

Origins of replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A Y-shaped region on a replicating DNA molecule where the parental strands are being unwound and new strands are being synthesized.

A

Replication fork

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

An enzyme that untwists the double helix of DNA at replication forks, separating the two strands and making them available as template strands.

A

Helicase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

A protein that binds to the unpaired DNA strands during DNA replication, stabilizing them and holding them apart while they serve as templates for the synthesis of complementary strands of DNA.

A

Single-strand binding protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

A protein that breaks, swivels, and rejoins DNA strands.

A

Topoisomerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

A short polynucleotide with a free 3′ end, bound by complementary base pairing to the template strand and elongated with DNA nucleotides during DNA replication.

A

Primer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

An enzyme that joins RNA nucleotides to make a primer during DNA replication, using the parental DNA strand as a template.

A

Primase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

An enzyme that catalyzes the elongation of new DNA (for example, at a replication fork) by the addition of nucleotides to the 3′ end of an existing chain.

A

DNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The new complementary DNA strand synthesized continuously along the template strand toward the replication fork in the mandatory 5′→3′ direction.

A

Leading strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A discontinuously synthesized DNA strand that elongates by means of Okazaki fragments, each synthesized in a 5′→3′ direction away from the replication fork.

A

Lagging strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A short segment of DNA synthesized away from the replication fork on a template strand during DNA replication.

A

Okazaki fragment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3′ end of one DNA fragment (such as an Okazaki fragment) to the 5′ end of another DNA fragment

A

DNA ligase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The cellular process that uses specific enzymes to remove and replace incorrectly paired nucleotides.

A

Mismatch repair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

An enzyme that cuts DNA or RNA, either removing one or a few bases or hydrolyzing the DNA or RNA completely into its component nucleotides.

A

Nuclease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The tandemly repetitive DNA at the end of a eukaryotic chromosome’s DNA molecule.

A

Telomere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The complex of DNA and proteins that makes up eukaryotic chromosomes.

A

Chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Eukaryotic chromatin that remains highly compacted during interphase and is generally not transcribed.

A

Heterochromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The less condensed form of eukaryotic chromatin that is available for transcription.

A

Euchromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
The synthesis of RNA using a DNA template.
Transcription
26
A type of RNA, synthesized using a DNA template, that attaches to ribosomes in the cytoplasm and specifies the primary structure of a protein.
Messenger rna
27
The synthesis of a polypeptide using the genetic information encoded in an mRNA molecule. There is a change of “language” from nucleotides to amino acids.
Translation
28
A complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm; consists of a large and a small subunit.
Ribosome
29
An initial RNA transcript from any gene; also called pre-mRNA when transcribed from a protein-coding gene.
Primary transcript
30
A genetic information system in which a series of three-nucleotide-long words specifies a sequence of amino acids for a polypeptide chain.
Triplet code
31
The DNA strand that provides the pattern, or template, for ordering, by complementary base pairing, the sequence of nucleotides in an RNA transcript.
Template strand
32
A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal
Codon
33
Nontemplate strand of DNA, which has the same sequence as the mRNA except it has thymine (T) instead of uracil (U).
Coding strand
34
On an mRNA, the triplet grouping of ribonucleotides used by the translation machinery during polypeptide synthesis.
Reading frame
35
An enzyme that links ribonucleotides into a growing RNA chain during transcription, based on complementary binding to nucleotides on a DNA template strand.
RNA polymerase
36
A specific nucleotide sequence in the DNA of a gene that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place.
Promoter
37
In bacteria, a sequence of nucleotides in DNA that marks the end of a gene and signals RNA polymerase to release the newly made RNA molecule and detach from the DNA.
Terminator
38
A region of DNA that is transcribed into an RNA molecule.
Transcription unit
39
In transcription, the nucleotide position on the promoter where RNA polymerase begins synthesis of RNA.
Start point
40
A regulatory protein that binds to DNA and affects transcription of specific genes.
Transcription factor
41
The completed assembly of transcription factors and RNA polymerase bound to a promoter.
Transcription initiation complex
42
A DNA sequence in eukaryotic promoters crucial in forming the transcription initiation complex.
TATA box
43
Modification of RNA primary transcripts, including splicing out of introns, joining together of exons, and alteration of the 5′ and 3′ ends.
RNA processing
44
A modified form of guanine nucleotide added onto the 5′ end of a pre-mRNA molecule.
5’ cap
45
A sequence of 50–250 adenine nucleotides added onto the 3′ end of a pre-mRNA molecule.
Poly-A tail
46
After synthesis of a eukaryotic primary RNA transcript, the removal of portions of the transcript (introns) that will not be included in the mRNA and the joining together of the remaining portions (exons).
RNA splicing
47
A noncoding, intervening sequence within a primary transcript that is removed from the transcript during RNA processing
Intron
48
A sequence within a primary transcript that remains in the RNA after RNA processing
Exon
49
A large complex made up of proteins and RNA molecules that splices RNA by interacting with the ends of an RNA intron, releasing the intron and joining the two adjacent exons.
Spliceosome
50
An RNA molecule that functions as an enzyme, such as an intron that catalyzes its own removal during RNA splicing.
Ribozyme
51
A type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns.
Alternative RNA splicing
52
An RNA molecule that functions as a translator between nucleic acid and protein languages by picking up a specific amino acid and carrying it to the ribosome, where the tRNA recognizes the appropriate codon in the mRNA.
Transfer rna
53
A nucleotide triplet at one end of a tRNA molecule that base-pairs with a particular complementary codon on an mRNA molecule.
Anticodon
54
An enzyme that joins each amino acid to the appropriate tRNA.
Aminoacetyl-tRNA synthetase
55
Flexibility in the base-pairing rules in which the nucleotide at the 5′ end of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3′ end) of a codon.
Wobble
56
RNA molecules that, together with proteins, make up ribosomes
Ribosomsl rna
57
One of a ribosome’s three binding sites for tRNA during translation.
P site
58
One of a ribosome’s three binding sites for tRNA during translation.
A site
59
One of a ribosome’s three binding sites for tRNA during translation.
E site
60
A sequence of about 20 amino acids at or near the leading (amino) end of a polypeptide that targets it to the endoplasmic reticulum or other organelles in a eukaryotic cell.
Signal peptide
61
A protein-RNA complex that recognizes a signal peptide as it emerges from a ribosome and helps direct the ribosome to the endoplasmic reticulum (ER) by binding to a receptor protein on the ER.
Signal-recognition particle
62
A group of several ribosomes attached to, and translating, the same messenger RNA molecule.
Polyribosome
63
A change in the nucleotide sequence of an organism’s DNA or in the DNA or RNA of a virus.
Mutations
64
A change in a single nucleotide pair of a gene
Point mutation
65
A type of point mutation in which one nucleotide in a DNA strand and its partner in the complementary strand are replaced by another pair of nucleotides.
Nucleotide-pair substitution
66
silent mutation | A nucleotide-pair substitution that has no observable effect on the phenotype
Silent mutation
67
A nucleotide-pair substitution that results in a codon that codes for a different amino acid.
Missense mutation
68
A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.
Nonsense mutation
69
A mutation involving the addition of one or more nucleotide pairs to a gene.
Insertion
70
A deficiency in a chromosome resulting from the loss of a fragment through breakage.
Deletion
71
A mutation occurring when nucleotides are inserted in or deleted from a gene and the number inserted or deleted is not a multiple of three, resulting in the improper grouping of the subsequent nucleotides into codons.
Frameshift mutation
72
A chemical or physical agent that interacts with DNA and can cause a mutation.
Mutagen
73
In bacterial and phage DNA, a sequence of nucleotides near the start of an operon to which an active repressor can attach.
Operator
74
A unit of genetic function found in bacteria and phages, consisting of a promoter, an operator, and a coordinately regulated cluster of genes whose products function in a common pathway.
Operon
75
A protein that inhibits gene transcription. In prokaryotes, repressors bind to the DNA in or near the promoter
Repressor
76
A gene that codes for a protein, such as a repressor, that controls the transcription of another gene or group of genes.
Regulatory gene
77
A small molecule that binds to a bacterial repressor protein and changes the protein’s shape, allowing it to bind to the operator and switch an operon off.
Corepressor
78
A specific small molecule that binds to a bacterial repressor protein and changes the repressor’s shape so that it cannot bind to an operator, thus switching an operon on.
Inducer
79
Cyclic adenosine monophosphate, a ring-shaped molecule made from ATP that is a common intracellular signaling molecule (second messenger) in eukaryotic cells.
Cyclic AMP
80
The expression of different sets of genes by cells with the same genome.
Differential gene expression.
81
The attachment of acetyl groups to certain amino acids of histone proteins.
His tone acetylation
82
The presence of methyl groups on the DNA bases (usually cytosine) of plants, animals, and fungi.
DNA methylation
83
Inheritance of traits transmitted by mechanisms that do not involve the nucleotide sequence.
Epigenetic inheritence
84
A segment of noncoding DNA that helps regulate transcription of a gene by serving as a binding site for a transcription factor.
Control element
85
A segment of eukaryotic DNA containing multiple control elements, usually located far from the gene whose transcription it regulates
Enhancer
86
A type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns.
Alternative RNA splicing
87
A small, single-stranded RNA molecule, generated from a double-stranded RNA precursor.
MicroRNA
88
One of multiple small, single-stranded RNA molecules generated by cellular machinery from a long, linear, double-stranded RNA molecule.
small Interfering rna
89
A mechanism for silencing the expression of specific genes.
RNA interference
90
An RNA between 200 and hundreds of thousands of nucleotides in length that does not code for protein but is expressed at significant levels.
Long noncoding rna
91
The process by which a cell or group of cells becomes specialized in structure and function.
Differentiation
92
The development of the form of an organism and its structures.
Morphogenesis
93
A maternal substance, such as a protein or RNA, that when placed into an egg influences the course of early development by regulating the expression of genes that affect the developmental fate of cells.
Cytoplasmic determinant
94
A process in which a group of cells or tissues influences the development of another group through close-range interactions.
Induction
95
The progressive restriction of developmental potential in which the possible fate of each cell becomes more limited as an embryo develops.
Determination
96
The development of a multicellular organism’s spatial organization, the arrangement of organs and tissues in their characteristic places in three-dimensional space.
Pattern formation
97
Molecular cues that control pattern formation in an animal or plant embryonic structure by indicating a cell’s location relative to the organism’s body axes.
Positional formation
98
Any of the master regulatory genes that control placement and spatial organization of body parts in animals, plants, and fungi by controlling the developmental fate of groups of cells.
Homeotic gene
99
A mutation with a phenotype leading to death of an embryo or larva.
Embryonic lethal
100
A gene that, when mutant in the mother, results in a mutant phenotype in the offspring, regardless of the offspring’s genotype.
Maternal effect gene
101
A maternal effect gene that codes for a protein responsible for specifying the anterior end in Drosophila melanogaster.
Bicoid
102
A substance, such as Bicoid protein in Drosophila, that provides positional information in the form of a concentration gradient along an embryonic axis.
Morphogen
103
A gene found in viral or cellular genomes that is involved in triggering molecular events that can lead to cancer.
Oncogene
104
A normal cellular gene that has the potential to become an oncogene.
Proto-oncogene
105
A gene whose protein product inhibits cell division, thereby preventing the uncontrolled cell growth that contributes to cancer.
Tumor suppressor gene
106
A gene that codes for Ras, a G protein that relays a growth signal from a growth factor receptor on the plasma membrane to a cascade of protein kinases, ultimately resulting in stimulation of the cell cycle.
Rae gene
107
A tumor-suppressor gene that codes for a specific transcription factor that promotes the synthesis of proteins that inhibit the cell cycle.
P53 gene