Molecular Genetics Flashcards
The following molecule (two-ring structure) is a
Purine
At the end of meiosis I, the daughter cells are ____ and each chromosome contain(s)
__ sister chromatid(s)
haploid; 2
The difference between general and specific transcription factors is
general transcription factors are required to transcribe all protein-coding genes
Which of the following is not a demonstration of genetic equivalence?
A) A clipping from a branch of a rose bush is planted in the ground and grows into another rose
bush.
B) a culture of bacteria gaining resistance to a specific antibiotic.
C) The nucleus from a sheep mammary cell is inserted into an enucleated egg cell to form a
clone of the original animal.
D) A skin cell is reprogrammed to become an induced pluripotent stem cell (iPS cell).
A culture of bacteria gaining resistance to a specific antibiotic
DNA polymerase III is an enzyme that catalyzes the synthesis of DNA. Which phase of
the cell cycle is DNA polymerase III active?
Interphase - S
Gametes are ______, and they fuse during the process of ____ to create a _____ cell
haploid; fertilization; diploid
If Hox genes that code for the head swap places with the Hox genes that code for the
abdomen
the abdomen will develop where the head does typically
Histone acetylation leads to the formation of
Euchromatin and increased gene expression
Explain the difference between enhancer and silencer sequences
Enhancer sequences bind to activator proteins/transcription factors and increase gene expression while silencer sequences bind to repressor proteins/transcription factors and decrease gene
expression.
A specific cancer cell spends 4 hours in G1 phase, 2 hours in S phase, 2 hours in G2 phase,
and 30 minutes in M phase. If a pulse-chase experiment were performed with radioactive nucleotides on an asynchronous culture of such cells, what percentage of mitotic cells would be radiolabeled 9 hours after the pulse?
0 percent
Cigarette smoking leads to changes in DNA methylation. Which nucleotides in DNA are
methylated, and explain how DNA methylation alters gene expression
- Cytosine
- Methylation decreases gene expression by inhibiting protein/transcription factor binding
Which model system used by Hershey and Chase helped confirm that DNA provides genetic
information?
Bacteriophage infecting bacteria
Explain why radioactive phosphorus exclusively labels DNA and not proteins
Phosphorus is found in the backbone of DNA, and not found in any amino acid; thus would not label
proteins
Meselson and Stahl provided the first evidence for DNA replication by growing bacteria in media
containing heavy nitrogen, and following growth in media with light nitrogen. After each round of replication, the DNA was separated by centrifugation. Circle the centrifugation tube that would result after one round of replication in media containing light nitrogen
Heavy/Light (one line in middle)
Explain what is meant by the concept of semi-conservative DNA replication
When DNA is copied/replicated, one strand is used as a template to synthesize a new strand. So in a newly made double helix, one parental strand is conserved and pared with a newly synthesized strand
