Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology > genetics > Flashcards

genetics Flashcards

1
Q

What makes up a nucleotide?

A

phosphate group, sugar, nitrogenous base

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

what nucleotides are purines?

A

adenine and guanine

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

what nucleotides are pyrimidines?

A

uracil, thymine, cytosine

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

if the molecule is DNA what hangs off of the 2’ ?

A

H

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

if the molecule is RNA what hangs off of the 2’ ?

A

OH(hydroxyl)

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

how are nucleotides added?

A

5’ to 3’

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

what bonds as used to add nucleotides?

A

phosphodiester bonds

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

what stage of the cell cycle does DNA get replicated?

A

S phase

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

what does semi conservative mean?

A

one newly synthesized strand and one old strand

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

DNA replication is….?

A

semi conservative

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

DNA in prokaryotic vs eukaryotic cells

A

prokaryotic
-genome is in the form of a circular, double-stranded -DNA molecule
-no nucleus, but a region containing the DNA called the nucleoid
-different enzymes
-some prokaryotes have plasmids

Eukaryotic
-more DNA
-DNA needs to be compacted
-histones (proteins) help in the winding and folding of DNA

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

what enzymes are used during initiation phase of DNA replication

A

TOPOISOMERASE, HELICASE, BINDING PROTEINS

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

what enzymes are used during elongation phase of DNA replication

A

DNA POLYMERASE III, PRIMASE, DNA POLYMERASE I, LIGASE

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

what enzymes are used during termination phase of DNA replication

A

none. all enzymes are removed from completed DNA strands

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

what is Helicase

A

enzymes that unravel and separate the double-stranded DNA

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

what do binding proteins and topoisomerase do?

A

they help to stabilize the strands of DNA

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

Replication bubble

A

forms as strands of DNA separate

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

what is the Replication fork

A

each end of the bubble
where strands are still attatched

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

what does Primase do

A

attaches RNA primers on each strand of DNA

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

what does DNA polymerase III do

A

begins adding nucleotides that are complementary to the template (original) strand

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

role of DNA polymerase I

A

-has the ability to cut and remove all RNA primers.
-It can then insert DNA to replace the RNA

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

purpose of DNA Ligase

A

this enzymes reconnects the newly inserted DNA with the rest of the synthesized strand.

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

Mispairing of nucleotides

A

Sometimes a nucleotide can pair up to a different nucleotide (ex. C to A) due to the presence of rare isomers of nucleotides (due to a tautomeric shift) or the physical misalignment of nucleotides during pairing (wobble).

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

Strand slippage

A

Sometimes strands can loop out resulting in either the addition or deletion of nucleotides in the newly synthesized strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
MISMATCH REPAIR
Mismatch repair occurs shortly after replication of the newly synthesized DNA strand. A specialized group of enzymes (Mut proteins) target deformities in the DNA strands. Using the parent strand as a guide, these enzymes remove incorrect nucleotides from the new (daughter) DNA strand.
26
Telomeres
non-coding regions found at the ends of our chromosomes
27
Introns
non-coding regions within a gene that are removed before the gene is expressed
28
p arm
shorter arm of the chromosome
29
q arm
longer arm of the chromosome
30
Gene Locus
the location of a gene on a chromosome
31
what is the central dogma (principle) of genetics?
DNA to RNA to Protein
32
Messenger RNA (mRNA)
a family of RNA molecules that carry coding instructions from DNA to the ribosomes that create protein.
33
Stop codons
UAG, UAA, and UGA
34
Transcription
Transcription takes place in the nucleus where mRNA is transcribed from the template (or antisense strand).
35
Translation
Translation takes place in the ribosome which begins translating codons. Ribosomes match up the codon to the corresponding amino acid starting with a start codon and it continues reading the mRNA strand one codon (3 nucleotides) at a time with each codon coding for a specific amino acid. This creates a chain of amino acids (polypeptide)! Translation stops once a stop codon is reached.
36
where does transcription take place?
in the nucleus
37
what is the purpose of transcription?
to produce an RNA copy of a small section of DNA.
38
what is the purpose of RNA polymerase and transcription factors?
to unwind the double-stranded DNA and connects to the antisense DNA strand at a particular site
39
Transcription factors
proteins that bind with the RNA polymerase and help activate and control the rate of transcription.
40
Transcription - Elongation
-the RNA polymerase complex begins synthesizing mRNA strand in the 5’ to 3’ direction -several strands of mRNA can be produced at once - there is no proofreading function - the RNA polymerase complex continues until it reaches a stop sequence where it then releases from the DNA.
41
Transcription -Termination
1- at the stop sequence RNA polymerases detach 2- DNA molecule reforms double helix structure
42
what is added to mRNA before it leaves the cell
-addition of a 5’ cap -3’ poly-A tai
43
tRNA
a folded strand of RNA that contains an anticodon region (written in 3’ to 5’) that matches up with a specific mRNA codon sequence and a region to carry an amino acid. Specific enzymes will attach the appropriate amino acid to the corresponding anticodon.
44
initiation- translation
1- small and large ribosomal subunits assemble along with the initiator tRNA around the start codon on the mRNA strand. - this initiator tRNA (with methionine) sits in the P site of the ribosome
45
ELONGATION- translation
-tRNA with the corresponding anticodon for the next 3 nucleotides in the mRNA sequence moves into the A (amino) site in the ribosome -amino acid(s) from the tRNA in the P (peptide) site bonds (peptide bond) with the incoming amino acid positioned in the A site. the ribosome moves -another 3 nucleotides (one codon) along the mRNA in the 5’ to 3’ direction -tRNAs within the ribosome shift over one position so that the A site is again open to receive another tRNA. -tRNA found in the E site will exit the ribosome
46
termination-TRANSLATION
-a stop codon signals for the separation and release of the polypeptide chain and the disassembly of the ribosome -the polypeptide goes to fold through its secondary, tertiary and quaternary (if applicable) structures
47
what is a mutation?
A mutation is a permanent change in the nucleotide sequence of DNA
48
what is as Single-gene mutation?
a mutation that involves changes in the nucleotide sequence of one gene
49
what is a Chromosome mutation?
a mutation that involves changes in chromosomes and may involve many genes
50
what is a Point mutation?
a mutation involving a single base pair substitution
51
what is a Frameshift mutation?
a mutation caused by the addition or deletion of a number of nucleotides not divisible by three, resulting in a change in the reading frame
52
what is a Silent mutation?
a mutation that does not change the amino acid sequence of a protein
53
what is a Missense mutation?
a mutation that changes the amino acid sequence of a protein
54
Nonsense mutation
a mutation that shortens a protein by introducing a stop codon
55
Mutagen
increases the rate of changes to the DNA sequence of an organism’s genome
56
what is a Spontaneous Mutations?
occur naturally in the cell during regular cellular activity (ex. replication, mitosis, meiosis)
57
what is a Induced Mutations ?
are caused by outside environmental factors ex. chemical and physical mutagens.
58
what is a Transposon?
a short segment of DNA capable of moving within the genome of an organism
59
what is the operator?
The operator is the DNA region that can inhibit the transcription of the operon when a repressor binds to the operator site.
60
what is The CAP-binding site
The CAP-binding site helps to speed up transcription.
61
what is The promoter region?
The promoter region is where the RNA polymerase binds in order start transcription.
62
what happens in the absence of lactose?
In the absence of lactose, repressors bind to the operator site and stops the transcription of the genes (operon).
63
gene expression in prokaryotes vs eukaryotes
prokaryotes -genes are grouped into operons -each operon is controlled by its own regulatory;atory region -RNA polymerase can directly bind to DNA -small number of transcription factors eukaryotes -genes not grouped -each gene controlled by its own promoter/regulatory region -many different transcription factors -transcription factors must be in place first on promoter region for RNA polymerase to bind to DNA
64
what is an operon?
a unit made up of linked genes which is thought to regulate other genes responsible for protein synthesis.
65
PCR steps
-Increasing the temperature of the DNA sample helps to separate the double-stranded DNA -The sample is cooled and DNA primers are allowed to bind to specific sequences on the separated strands of DNA -The temperature is increased again and the taq polymerase enzymes go to work in synthesizing the complementary strands starting from the DNA primers. Taq polymerase is a DNA polymerase that works well in higher temperatures. -The sample is then cooled temporarily until this process is repeated again several times.
66
is DNA (+) or (-)
(-)
67
what is Gel electrophoresis ?
Gel electrophoresis is a method that uses an electric field to pull fragments of DNA (*STRs) through a gel
68
how are DNA fragments sorted in Gel electrophoresis?
DNA fragments are sorted according to their size as smaller fragments travel through the gel more quickly than larger ones
69
what needs to happen before gel electrophoresis is done?
Typically DNA samples need to be amplified (more copies) using PCR and then cut with restriction enzymes to form desired DNA fragments.
70
what is The CRISPR/Cas system used for?
The CRISPR/Cas system has been used for gene editing (adding, disrupting or changing the sequence of specific genes).
71
what is the CRISPR/Cas9 system?
The CRISPR/CAS9 system is a prokaryotic (bacterial) immune system that generates resistance to invading genetic elements such as plasmids and phages, and provides a form of acquired immunity.
72
how does CRISPER/cas9 program allow gene editing?
This allows scientists to program CRISPR/Cas9 to cut a specific sequence and allow for cutting out genes and allowing new genes to be inserted in their place

biology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions