BIO 211G Exam 4
S mutation in Glc-Nac-1-PTS causes
I-cell disease
Which of the following best describes the proton motive force?
the gradient of protons across the inner mitochondria membrane
Which of the following proteins has an ER signal peptide?
the insulin receptor and insulin
How is the next amino acid added to a growing protein?
the protein is transferred from the P site tRNA to the amino acid on the A site tRNA
What is the targeting sequence for a cytoplasmic protein?
there is no targeting sequence for cytoplasmic proteins
what binds to the promotor?
transciption factors
The sequence of a portion of a template strand f DNA is shown. What is the amino acid sequence encoded by this DNA sequence? TAC TTC AAA
Met Lys Phe
During glycolysis, which molecule accepts electrons?
NAD+
During the citric acid cycle, which molecule(s) accept(s) electrons?
NAD+and FAD
At the end of the citric acid cycle, which of the following molecules is holding electrons from glucose?
NADH
What molecule donates electrons to the electron transport chain during cellular respiration?
NADH
What accepts electrons at the bottom of the electron transport chain during cellular respiration?
O2
What is the final electron acceptor in cellular respiration?
O2
The product of transcription is a_____ molecule
RNA
Which of the following gene fragments encodes a peroxisomal targeting sequence? (the DNA sequence of the template strand corresponding to the three codons encoding the three C-terminus amino acids is shown)
TCG TTC GAA AGG TTT GAT AGA TTC AAT
which of the following is a mRNA codon that is specifically recognized by release factor?
UAA
which of the following is added to RNA after transcription has occurred (as part of RNA processing)?
a 5' cap
Which of the following is out likely to cause Duchenne Muscular Dystrophy?
a nonsense mutation in exon 45 (out of 79 exons)
What does release factor recognize?
a stop codon in the A site
What signal sequences are part of insulin?
an Er signal peptide
How can O2 be characterized in terms of cellular respiration?
an acceptor
How can glucose be described?
as a reduced molecule; as an electron donor
Why are peroxisomal proteins found in the cytoplasm in Zellweger syndrome?
because PEX1 is mutated
What protein is mutated in people with Duchenne Muscular Dystrophy (DMD)
dystrophin
Which of the following terms apply to ATP synthesis?
endergonic
During translation, how do "empty" tRNAs leave the ribosome?
from the E site
Which of the following is the correct order of molecules from most reduced to most oxidized?
glucose--> pyruvate--> acetyl Coa--> Co2
a peroxisomal protein has an intact peroxisomal targeting sequence, but there is a mutation in PEX1 that destroys PEX1 function. Where will the peroxisomal protein be found?
in the cytoplasm
Where does the "key" phosphorylation event that generates the lysosomal targeting sequence occur?
in the golgi
which sequence(s) is/are removed from pre-nmRNA as it is processed to mature mRNA?
introns
What happens to glucose during glycolysis?
it becomes partially oxidized to pyruvate
What happens when NAD+ accepts electrons?
it becomes reduced to NADH
How does a nonsense mutation impact transcription?
it does not impact transciption
In order for a promoter mutation to be the cause of Duchenne Muscular Dystrophy (DMD), what would the mutation have to do to the promoter?
make the promoter "weaker" than normal
What type of mutation results in a change of one amino act to another amino acid in the encoded protein?
missense
Does RNA polymerase have an Er signal peptide
no
a wild type protein is 156 amino acids in length, and has a valine as its 78th amino acid. A mutant version of the protein is much shorter-only 77 amino acids in length. The mutant version is otherwise identical to the wild type. What type of mutation occurred at codon 78?
nonsense
Which type(s) of mutation change(s) the DNA sequence?
nonsense, silent, and missense.
A mutation cause the dystrophin protein to be shorter than normal. What type of mutation, and where, could cause this?
nonsense; exon
A particular dystrophin gene has a mutation in the promoter, a mutation in an exon and mutation in an intron. Which of these will be present in the mature mRNA?
only the exon mutation
a protein has an ER signal peptide as its only targeting sequence. Where will this protein be found?
outside the cell (because it will be secreted)
Which of the following is NOT a part of the endomembrane system?
peroxisomes
How is the proton olive force (PMF) generated?
proton pumping by the ETC from the mitochondrial matrix to the IMS
What is dystrophin important for?
supporting muscle structure and function
Which type of RNA brings the brings the next amino acid to the ribosome?
tRNA
Where does a tRNA enter the ribosome?
the A site
What is the immediate (direct) source of energy for ATP synthesis by ATP synthase?
the PMF
A portion of a gene has the sequence 5' ATTCAG 3'. What is the complementary RNA sequence?
3' UAAGUC 5'
What is the release factor?
A specialized protein
Which stage(s) of cellular respiration occur(s)in the mitochondria?
ETC and citric acid cycle