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please answer all the questions: Question 4 Even though living organisms can be

ID: 132319 • Letter: P

Question

please answer all the questions:

Question 4

Even though living organisms can be highly conserved in gene sequence and functional metabolism, one reason there are major differences in the organisms themselves is

because all the exact same genes are expressed amongst different organisms

all of the above (except none of the above)

because timing of gene expressions is highly conserved amongst organism

because location of expression is specific to different organism

none of the above

Question 2

0 / 1 pts

Polymerase Chain Reaction (PCR) amplification

  

originally started with scientists moving tubes from a hot water bath, to a cool water bath, to a medium water bath by hand every 30 seconds for 3 hours

  

requires that you know the DNA sequence in which you are attempting to amplify

  

can be used to amplify RNA sequences with some slight differences to the protocol

  

requires that dNTPs be added to the tube as the cell is not present to provide them

   

all of these answers

Question 4

0 / 1 pts

You genetically removed the C-terminal coding region of your favorite protein/enzyme. When attempting to identify how your protein's function is affected by the loss of the C-terminal, you could

   

  

run a co-immunoprecipitation where you remove your favorite protein from suspension and all other proteins that are bound. Follow this step with running an SDS-PAGE gel and then visualizing the number of bands when compared to the wildtype version could demonstrate increased binding partners (additional bands) or decreased binding partners (less bands)

  

run an affinity collumn assuming you knew a ligand which can pull out your protein of choice and whatever proteins are bound to it. Follow this with eluting all bound proteins and run a mass spec to identify which protein are present and if they have changed with the C-terminus missing

  

discover the proper conditions to crystalize your protein and determine if the overall structure changes

   

all of these answers (except none of these answers)

   

none of these answers

IncorrectQuestion 5

0 / 1 pts

The concept of a hertiable molecule (that we now know is DNA) between cells

   

began in the 80s when we could copy DNA

  

had long been theorized before it could be demonstrated

   

occurred in the 1920s

   

occurred in the 1940s

IncorrectQuestion 6

0 / 1 pts

The beauty of complimentary base pairing is....

(One answer is better than the other)

  

if you know one side you know the other exact nucleotide

  

you can narrow down the opposing sides sequence to one of the other three nucleotides

  

Either side can be used to make the exact same RNA despite which direction the gene is read in

   

there is no beauty :(

IncorrectQuestion 7

0 / 1 pts

The human genome project demonstrated

   

how little of our DNA we have a known function for

  

that our genome was never attacked by transponable elements of DNA

   

that our genome is roughly 1 million nucleotides long

   

none of these answers

   

all of these answers (except none of these answers)

IncorrectQuestion 8

0 / 1 pts

Our understanding of RNA

   

was non-existent until 2000

  

started with the identification of a tRNA which suggested a method of converting DNA to protein

   

began to identify that DNA-->protein--> RNA

   

stopped growing after it's original discovery in the 70s

IncorrectQuestion 10

0 / 1 pts

Enzymes allow for chemical reactions to occur in the cell that may not naturally occur at the right place at the right time. They are exceptionally useful as

  

their activity can be regulated by post-tranlational modifications

  

they can be localized within a cell to increase localized activity

   

none of the answers

   

all of the answers (except none of the answers)

  

their active site can be highly specific to distinguish between molecules

Question 1

0 / 1 pts

The acetylation of lysines on the histone tails … (double check the book for this one as I think I mis-spoke during the lecture)

  

can be performed on methylated lysines only after they are first demethylated.

   

is a covalent modification and is thus irreversible.

  

recruits the heterochromatin protein HP1, resulting in the establishment of heterochromatin.

  

oosens the chromatin structure because it adds positive charges to the histone.

  

is sufficient for the formation of an open chromatin structure.

Question 3

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The position effect variegation (PEV) phenotype described in this chapter can be used to identify new genes that regulate heterochromatin formation. For instance, strains of Drosophila melanogaster with the White variegation phenotype have been subjected to mutagenesis to screen for dominant mutations (in other genes) that either enhance or suppress PEV, meaning the mutations result in either lower or higher red pigment production, respectively. Which of the following mutations is expected to be an enhancer of variegation?

  

A gain-of-function mutation in a gene encoding a histone methyl transferase that trimethylates lysine 9 on histone H3, resulting in a hyperactive form of the enzyme.

  

A gain-of-function mutation in a gene encoding a histone acetyl transferase that normally acetylates lysine 9 on histone H3, resulting in higher expression of the protein.

  

A loss-of-function mutation in a gene encoding a histone deacetylase that deacetylates lysine 9 on histone H3.

  

A mutation that results in the loss of function of the fly's HP1 (heterochromatin protein 1) gene.

Question 7

0 / 1 pts

Imagine a chromosome translocation event that brings a gene encoding a histone acetyl transferase enzyme from its original chromosomal location to a new one near heterochromatin. Which of the following scenarios is definitely NOT going to happen?

  

The gene gets silenced due to heterochromatin expansion, leading to the misregulation of gene expression for a number of critical genes.

  

The translocation event also brings along a chromatin barrier that can prevent heterochromatin expansion into the gene, and there is no phenotypic anomaly.

  

Since the gene encodes a histone acetyl transferase, it resists heterochromatin expansion by acetylating its own histones.

  

The level of the gene product decreases due to a position effect, leading to an imbalance in the chromatin state of the cell that results in the activation of programmed cell death.

Question 9

0 / 1 pts

Indicate which numbered feature (1 to 5) in the schematic drawing below of the DNA double helix corresponds to each of the following. Your answer would be a five-digit number composed of digits 1 to 5 only, e.g. 52431.

( )     Hydrogen-bonding

( )     Covalent linkage

( )     Phosphate group

( )     Nitrogen-containing base

( )     Deoxyribose sugar

   

12345

   

32415

   

43215

   

43512

Question 10

0 / 1 pts

Most fish genomes are at least 1 billion nucleotide pairs long. However, the genome of the puffer fish Fugu rubripes is quite small at only about 0.4 billion nucleotide pairs, even though the number of Fugu genes is estimated to be comparable to that of its relatives which have larger genomes. What do you think mainly accounts for the Fugu genome being this small?

  

Evolutionary advantage of extremely small exon sizes in the Fugu lineage

  

Unusual disappearance of all intronic sequences from the Fugu genome

  

Increased abundance of transposable elements in the Fugu genome

  

Increased occurrence of mitotic whole-chromosome loss in the Fugu lineage

  

Low relative rate of DNA addition compared to DNA loss in the Fugu lineage

because all the exact same genes are expressed amongst different organisms

all of the above (except none of the above)

5 1 4 3

Explanation / Answer

4. Options C and D are correct.

The phenotypic differences among different organisms is due to differences in spatial and temporal gene expression patterns.

2. Option E is correct.

All the given options are true regarding PCR.

4. Option E is correct.

All the given procedures can be used to determine the effect of the mutation on the protein function.

5. Option D is correct.

The concept of heritable molecule occurred in the 1940s.

6. Option A is correct.

Sequence complementarity allows us to determine the sequence of unknown strand using the sequence of the known strand.

7. Option A is correct.

The HGP revealed that only a fraction of our genome contains coding sequences.