Mutations Practice Quiz

What is a mutation?

A mutation can be several things: Answer A mutation can be several things: A change in individual basses in a DNA strand. Additions – Frame Shift Deletions – Frame Shift Substitutions - three types Missense Nonsense Silent Can have large scale changes in a chromosome. Additions Deletions Substitutions/Crossing over/etc.

Frame shift mutations are very detrimental, whY?

Answer Every codon and amino acid is off throughout the rest of the protein.

Which substitution mutation is the worst. Which doesn’t matter at all Which substitution mutation is the worst? Which doesn’t matter at all? Which is minimally detrimental?

Answer Nonsense – This creates a stop codon causing the protein to stop being created, this is the worst. Missense – This is minimally detrimental, this is when an incorrect amino acid is added. Silent – this mutation doesn’t effect the protein at all, this is when a mutation occurs but the amino acid doesn’t change.

What would a chromosome look like with a large scale addition?

Answer It would be longer than normal on the karyotype

What would a substitution look like on a chromososme?

Answer The banding pattern would be abnormal, meaning it would be out of order and wouldn’t match the other sister chromatid.

What would a large scale deletion look like on a chromosome?

Answer It would be shorter/a section would be missing.

What is a Karyotype?

It is a picture of your DNA, Where the sister chromatids are lined up. Answer It is a picture of your DNA, Where the sister chromatids are lined up. Look at the karyotype to the right. Male or Female? Female (XX) What disorder is shown in the karyotype? Patau’s syndrome or Trisomy 13

What is nondisjunction?

Answer This is when chromosomes don’t split up normally in meiosis. This causes a egg or sperm cell to have an extra chromosome or be short a chromosome.

What disorder is a trisomy of chromosome 21?

Answer Down’s Syndrome

Can you have nondisjunction in the Sex chromosomes (pair 23)?

Answer Yes, Turner’s Syndrome and Kleinfelter’s syndrome are both caused by issues with the X and Y chromosome.

If an egg cell has two of chromosome 19, and it meets up with a sperm cell. How many total chromosomes will the resulting zygote have?

Answer 47

If an egg cell has one of chromosome 12, and it meets up with a sperm cell. How many total chromosomes will the resulting zygote have?

Answer 45

If you had to lose one chromosome, which one would you lose and why?

Answer 21/22 – they are the smallest chromosome, therefore they have the fewest genes.