A silent point mutation...
codes for the same amino acid, polypeptide does not change
A nonsense point mutation...
terminates the chain (stop codon)
A missense point mutation...
produces a different amino acid
How do you know if DNA was transcribed to RNA?
U is present in the RNA code
What is tRNA?
transfer RNA that carries the amino acids to the ribosome via the anticodon
What makes up the backbone of a DNA strand?
sugar and phosphate
What type of structure is thymine?
pyrimidine, single ring
What type of structure is adenine?
purine, double ring
What type of structure is guanine?
purine, double ring
What type of structure is cytosine?
pyrimidine, single ring
Which type of RNA carriers information from the nucleus into the cytoplasm?
mRNA
Describe gene expression via chromatin modification.
DNA methylation condense chromatin by adding methyl groups to the dna
During electrophoresis, why does DNA move toward the positive electrodes?
phosphate group on DNA have a negative charge
What procedure amplifies DNA?
PCR
Describe the semi-conservative model of DNA replication.
Both parent strands are copied. The daughter molecules have one parental and one new strand
If scientists do an experiment that prevents DNA from replicating properly, making the strands re-bond after they are separated by helicase, what is most affected by the experiment?
helicase
Describe initiation during transcription in prokaryotic cells.
RNA polymerase can bind directly to DNA
Describe initiation during transcription in eukaryotic cells.
RNA polymerase must bind to transcription factors
On the leading strand, DNAP III transcribes in what direction?
same as helicase
How many primers are used in transcription of the leading strand?
only one
What direction does the leading strand elongate?
5' to 3'
What would you expect if a chemical altered eukaryotic mRNA so there is no 5' cap added?
less protein in the cell because it is easily broken down when it leaves the nucleus
Describe gene expression in prokaryotes.
transcription and translation happen in the same place at the same time, ribosomal subunits are smaller
Describe gene expression in eukaryotes.
transcription happens in the nucleus, translation happens in the ribosomes/cytoplasm, ribosomal subunits are larger
In eukaryotic development, what is the physical process that gives an organism its shape?
morphogenesis
What is an operon?
promoter, operator, and gene
Describe termination of translation.
stop codon in the mRNA reaches the A site of a ribosome and release factor will hydrolyze the bond that holds the polypeptide
The E. coli operon is considered an...
inducible operon
Why must the lagging strand elongate using Okazaki fragments?
DNA polymerase can only move in the 3' to 5' direction
How does point mutation affect an enzyme's activity?
may change an amino acid or terminate the chain early; reduces the enzyme's ability to function
Describe transformation.
bacteria uptake DNA from their surroundings
Describe conjugation.
if bacteria contain an F factor, it can transfer DNA to a nearby cell via its pilus. If it transforms the F factor to the bacteria, it turns into an F+ donor and makes its own pilus
Describe transduction.
a virus injects its DNA into a bacterial cell, sometimes the DNA from the bacteria is incorporated into the viral DNA
Which of the following does NOT represent a differnece between gene expression in prokaryotes vs eukaryotes?
b. prokaryotic RNA polymerase moves across the DNA in a 3 to 5 direction
5 cap will not be added
the scientist would expect to find less protein A in the cell because it would be more easily broken down when leaving the nucleus
APE
translation; elongation
which of the following best describes termination of translation
when a stop codon in the mRNA reaches the A site of the ribosome and release factor will hydrolyze the bond that holds the polypeptide bond
why do okazaki fragments form?
DNA polymerase can only move in the 3 to 5 direction
A section of DNA at the replication fork reads as follows: 3’- ACTGATCTAAGC -5’. Primase places an RNA primer starting at the underlined nucleotide. What would be the correct primer sequence?
5’- UAGAUUCG -3’
according to the figures, what does the araC regulatory gene produce and where does it bind?
the araC protein; binds to the promoter
what type of operon is shown in figures 2 and 3?
inducible operon
researchers experimenting w cancer drug that rebonds DNA strands, what is most likely to be affected?
SSBPs
transduction def
viral transmission of genetic material
conjugation def
cell to cell transfer of DNA
transpostion
movement of DNA segments within and between DNA molecules
transformation
uptaking of DNA from a nearby cell
which of the following does not represent a componet of operon
d. repressor
used to be alt splicing
a. transcription; elongation
process w boxes
alternative splicing
what gene would you expect to see DOWNSTREAM of the operator in figures 2 and 3?
pAMP
metastasis
The spread of cancer cells from the place where they first formed to another part of the body
how does cadherin 22 promote metastasis?
hypoxic cancer cells to stick together and migrate collectively as a group
propose and explain one possible mechanism for how adh 1 could target and reduce cadherin 22 levels in cancer cells
the cellular signaling pathway can be toyed with and lead to impact the downstream signaling pathways and messes w the growth of the cancerness
large scale changes
chromosmal
small scale
nucleotides subs, insertions, deletions