genetic final study questions

How are proteins regulated after translation?

-inactive proteins can be activated by post-translational modification - proteins can be tagged with ubiquitin molecules and subsequently degraded -active proteins can be inactivated by allosteric regulation

A husband and wife have normal vision, although both of their fathers are red-green color blind, which is inherited an x-linked recessive condition. What is the probability that their first child will be normal vision and male?

0.25

Consider a species with a diploid (2n) number of 40 chromosomes. How many chromosomes would be found in a monoploid body cell?

20 (40/2)

Consider a species with a diploid (2n) number of 20 chromosomes. How many chromosomes would be found in a trisomic body cell?

21 (2n+1)

DNA polymerase has a _________ function (capability)

3' to 5' exonuclease

How many different gametes can be formed from the genotype AaBbCCDdEe?

32

Two elements of the eukaryotic mRNA transcript facilitate translation prior to initiation, the ____________ in addition to the ____________.

5' cap; ribosome binding site

Chrysanthemums have a haploid chromosome number of 9. How many chromosomes are found in octoploid chrysanthemum species?

72

Select the statements that accurately describe different ways that translocations could lead to cancer.

A translocation disrupts the sequence of a gene for a tumor suppressor protein. The resulting protein cannot function properly .-A gene for a protein that is involved in a mitotic checkpoint is placed next to the regulatory sequence of a different gene. The gene is now expressed at inappropriate times .-A new sequence is added to a proto oncogene. The modified gene now produces a new protein that increases the rate of cell division.

1. Consider 3 yellow, round peas labeled A,B and C. Each grown into a plant and crossed with a plant grown from a green wrinkled pea. Exactly 100 peas issuing from each cross were sorted into phenotypic classes as follows: A: 51 yellow, round 49 green, round B: 100 yellow, round C: 24 yellow, round 26 yellow, wrinlked 25 green, round 25 green, wrinkled What are genotypes of A, B and B

A= YyRR B=YYRR C=YyRr

examples of epigenetic modifications

DNA methylation,Histone acetylation, and phosphorylation

The enzyme responsible for the most of the nascent chain synthesis during DNA replication in E.coli is?

DNA poly 3

DNA polymerase II

DNA repair/ proofreading

In DNA synthesis, all base pairs of a genome are replicated. In the production of RNA, only a selected portion of bases of DNA in a genome are transcribed. In either a prokaryote or a eukaryote (your choice), explain how the process of transcription selectively results in a particular gene being transcribed into mRNA. Use appropriate terminology in your answer

Gene transcription is the first step in protein synthesis. A group of transcription factors assemble at the promoter region of DNA, and bind to TATA box to change its shape. This event exposes the binding sites of other transcription factors. After several of these events, RNA polymerase binds. The transcription factors selectively bind to the DNA regions to initiate the transcription of specific genes from specific sites.The binding of RNA polymerase to the promoter site starts the process of transcription. There are three different classes of RNA polymerases that bind to different promoter sites and transcribe different parts of genome. The terminator present at another end of the genome signals the completion of transcription, thus terminating the programme.In prokaryotes, the genes are transcribed in groups called operons, but in eukaryotes, the transcription of genes occurs individually.

Which description applies to epigenetic gene regulation?

Heritable changes in gene expression that occur without altering the DNA sequence

In prokaryotes and Eukaryotes describe what else is occurring as the RNA strand is being synthesized.

In prokaryotes, translation is beginning at the 5´ end while the 3´ end is still being transcribed. In eukaryotes, processing (capping, splicing) is occurring at the 5´ end while the 3´ end is still being transcribed

What best describes telomerase function?

Lengthens the 3' strand at teh end of a chromosoe without a template

Which phase of Meiosis is more similar to Mitosis?

Meiosis 2

An RNA primed DNA frament formed on the lagging strand

Okazaki fragment

Which of the following does not belong with the other four?" a) translocation b) deletion c) inversion d) duplication e) polyploidy

Polyploidy

Which of the following does not correctly match a structure with a process?

Primer-Transcription

A strong hairpin followed by a stretch of U nucleotides in 3' untranslated region of a prokaryotic RNA results in what?

Rho independent termination of transcription

A mutated eukaryotic cell contains a mutation in the middle of an exon in gene Q on a single allele. What will be the most likely result od this mutation?

The enzyme produced from Q gene would likely have less activity than normal

Two unlinked loci effect mouse hair color. CC or Cc mice have colored hair. Mice with genotype cc are albino because all pigment production and deposition of pigment in hair is blocked. At the second locus, the B allele (black coat) is dominant to the b allele (brown coat). A mouse with a black coat is mated with an albino mouse of genotype bbcc. Half of the offspring are albino, one quarter are black, and one quarter are brown. What is the genotype of the black parent? a) BBcc b) BbCc c) bbCC d) BBCC e) BbCC

The genotype of the black parent is BbCc.

The three versions of genetics

Transmission Genetics, Molecular and Dev Genetics, and Population/Evolutionary Genetics

If an affected male has all affected daughters and no affected sons, then what is the trait ?

X-linked dominant trait

In humans, many more males are affected by Duchene muscular dystrophy than females and these affected males typically come from unaffected parents. The likely inheritance pattern is?

X-linked recessive

In 1928, Fredrick Griffith's experiments with Streptococcus pneumoniae suggested that:

a heat killed bacteria could somehow "transform" live bacteria

DNA polymerase catalyzes teh formation of:

a phosphodiester bond between 3' OH and 5' phosphate of free dNTPS

In eukaryotes, high levels of transcription of a gene could be caused by:

an activator and enchancer

When an organism gains or loses one or more chromosomes but not a complete haploid set, the condition is known as:

aneuploidy

Rho factors

are responsible for the termination of transcription in prokaryotes

If an affected male has affected daughters and sons in about the same number as unaffected daughters and sons, the trait is likely to be an

autosomal dominant trait

The synthesis of DNA in the leading strand is ___________ and in the lagging strand it is ______________?

continuous; discontinuous

Posttranslational modification of proteins by ubiquitination leads to _________________ by the 28s proteasome

degeneration

If prokaryotic DNA polymerase 1 were muted so that all its enzymatic activites were inactive, which part of replication would be most affect?

deleting of Okazaki fragment using an RNA primer

How many chromosomes would be found in an allopolyploid (amphidiploid) plant if its original parents (progenitor species) had diploid numbers of 6 and 10 respectively?

diploid 8

The maximum percent recombination between two eukaryotic genes is usually 50%. Why doesn't it go higher?

each cross over event only recombines 2 of 4 chromatids present- so, there will always maximally 50% parental and 50% recombinant products

DNA polymerase 1

enzyme that replaces RNA primers with DNA nucleotides

Which of a woman's grandparents could not be the source of any of the genes on either of her X-chromosomes? a) mother's father b) Father's mother c) Mother's mother d) Father's father e) Mother's mother and mother's father

father's father

If a man is heterozygous for a gene, then he

has a pair of homologous chromosomes with different alleles for that gene

Human males are neither heterozygous nor homozygous fir alleles on the X chromosome, they are?

hemizygous

An anticodon is a sequence of three nucleotides that

is found on transfer RNA and is complementary to messenger RNA codons

Four types of RNA molecules that can result from transcription are?

mRNA, snRNA, rRNA, and tRNA

In Meselson and Stahl's experiment, the semiconservative nature of DNA synthesis was demonstrated by the fact when grown in 14N medium =, E.coli containing 15N labeled DNA produced:

only DNA of an intermediate density in the first replication cycle

Assembly of the replisome machinery begins at a specific location in prokaryotic and eukaryotic DNA termed the ?

origin of replication

A ______ is a short RNA molecule that binds to the DNA template and allows DNA polymerase to begin DNA synthesis. A _______ is responsible for creating this RNA molecule during initiation of DNA synthesis

primer; primase

A transfer of genetic material between non-homologous chromosomes is called:

reciprocal translation

The o subunit of RNA polymerase recognizes and denatures the A-T rich Pribnow box in the promotor step occurs?

step occurs during the initiation of transcription in E.coli

DNA polymerase III

synthesizes new DNA only in the 5' to 3' direction

Eukaryotic RNA pol 3 is responsible for transcribing?

tRNA and snRNA

Which of the following statements correctly describes telomerase? a) telomerase carries its own DNA template b) telomerase extends the 3' ends of the template strands of DNA in linear chromosomes c) telomerase separates the circular daughter strands in E. coli DNA replication d) telomerase unwinds the DNA in the pre-priming stage of DNA e) none of the above

telomerase extends the 3' ends of the template strands of DNA in linear chromosomes

Genetic recombination as a result of crossing over occurs more readily in genes:

that are located far apart on the same chromosome

DNA synthesis is said to be in a 5' to 3' direction. This means that:

the newly made DNA is produced in a 5' to 3' direction

Factor removes positivve supercoils ahead of the replication fork

topoisomerase

The synthesis of single-stranded messenger RNA using DNA template is called

transcription

Tortoise-shell cats have a patchwork coloration pattern and black spots. This pattern is an example of:

x-inactivation