Question 1

Exposure to ultraviolet (UV)light can alter DNA sequences in a cell.Uncorrected,these changes can lead to skin cancer.Individuals who have a mutation in a gene that produces DNA ________ protein may be at an increased risk for skin cancer.

Accepted Answer

The answer of Exposure to ultraviolet (UV)light can alter DNA...

Question 2

Put the following in order from smallest to largest.
-This is the smallest in size.

Accepted Answer

A base is the smallest unit, followed by a nucleotide, base pair, gene, and genome.

Question 3

A new copy of a double helix that is composed of a template strand and a newly replicated strand of DNA is created using ________ replication.

Accepted Answer

The answer of A new copy of a double helix...

Question 4

A scientist used CRISPR-Cas9 to inactivate the pol gene for DNA polymerase in the porcine endogenous retrovirus (PERV)sequences of a pig embryo.The resulting pig embryo cells were then placed in proximity of human cells,but there was no infection of the human cells by the PERVs.Why were the PERVs no longer able to infect the human cells?

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The answer of A scientist used CRISPR-Cas9 to inactivate the...

Question 5

Compare the segment of DNA for normal hemoglobin DNA with the segment for sickle-cell hemoglobin DNA below.Sickle-cell disease is caused by a ________ mutation.

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The answer of Compare the segment of DNA for normal...

Question 6

A chemical is found that binds to a replicating strand of DNA but does not allow the next nucleotide to bind to the growing chain.Explain how this chemical would affect cell division.

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The answer of A chemical is found that binds to...

Question 7

Describe the building blocks of DNA and how they are bonded together to form the DNA double helix.

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The answer of Describe the building blocks of DNA and...

Question 8

You are working for a pharmaceutical company that hopes to produce genetically engineered human pancreatic amylase from rapidly reproducing E.coli cells.Your colleague has worked for months to isolate a minute amount of DNA that she suspects contains the gene for human pancreatic amylase.You need more of this DNA for testing and evaluation.Describe how you can easily produce millions of exact copies of this DNA.

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The answer of You are working for a pharmaceutical company...

Question 9

A mutation is due to the addition of two bases in a strand of DNA.This is called a(n)________.

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The answer of A mutation is due to the addition...

Question 10

Nitrous acid is a chemical that can react with DNA and change cytosine to uracil.If a cell is exposed to nitrous acid and some of the cytosine nucleotides in a gene are converted to uracil nucleotides,what should happen when that cell replicates?

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The answer of Nitrous acid is a chemical that can...

Question 11

Using the figure below,describe how the two guide RNA molecules in the CRISPR-Cas9 system find the target DNA sequence.

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The answer of Using the figure below,describe how the two...

Question 12

When studying genomes of organisms,scientists often will only list the sequence of a single strand.Explain why the sequence of the second strand would be unnecessary information.

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The answer of When studying genomes of organisms,scientists often will...

Question 13

What would you expect to find if you examined the DNA base-pair sequence of the allele for a mutated cystic fibrosis transmembrane regulator gene (CFTR)and compared it to the DNA base-pair sequence of the allele for a fully functional CFTR gene?

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The answer of What would you expect to find if...

Question 14

Cooling cycles during PCR amplification of DNA enable enzymes to build two new strands of ________ through ________ base-pairing.

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The answer of Cooling cycles during PCR amplification of DNA...

Question 15

A scientist adds a single polymerase and primer to a polymerase chain reaction (PCR)but does not add nucleotides.How many strands would be present after three replications if a single original strand was present? Explain your answer.

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The answer of A scientist adds a single polymerase and...

Question 16

The cells in tissue that produces mammalian sperm cells are rapidly reproducing to provide a continuous supply of sperm cells.Considering the effect of heat on double-stranded DNA,what is likely to happen to the production of mutation free sperm cells if this tissue is kept at a significantly warmer temperature than usual?

Accepted Answer

The answer of The cells in tissue that produces mammalian...

Question 17

Put the following in order from smallest to largest.
-This is the second smallest in size.

Accepted Answer

A nucleotide is the smallest unit of a nucleic acid, such as DNA or RNA.

Question 18

A chemical that disrupts hydrogen bonds is added to a test tube containing DNA.What would be the result of this reaction?

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The answer of A chemical that disrupts hydrogen bonds is...

Question 19

Being in the sun for short stretches of time is not as likely to cause mutations as is being in the sun for long stretches of time.Explain why longer exposure to ultraviolet (UV)is more likely to cause mutations.

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The answer of Being in the sun for short stretches...

Question 20

Are mutations always harmful? Justify your answer using an example.

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The answer of Are mutations always harmful? Justify your answer...

Quiz 9: What Genes Are