Question

. In the LL recording, I mention that the redundancy of the genetic code is like “Nature’s Safety Net”… Explain what that means. (3pts)

3. Which substitution mutation has the potential to cause more damage? (1pts)
a) substitution of 3rd N-base to go from AUU to AUC
b) substitution of 3rd N-base to go from AGU to AGC
c) substitution of 3rd N-base to go from AAC to AAA

4. Explain WHY: (3pts)________________________

Answer 1

5. How would the following insertion mutation of an adenine in the 3rd codon affect the amino acid chain produced in the following sequence… (2pts)
Original mRNA strand- AUG GCU UGG CCC UAA
Mutated mRNA strand- AUG GCU UAG GCC CUA A
a) The ribosome would not be able to translate the mRNA with this mutation
b) The ribosome would make proline instead of alanine
c) The ribosome would receive a stop codon at an earlier spot, so the correct protein would not be made


For each of the following, please indicate if the mutation described would be inherited (A) or not inherited (B) . (3pts total)
B 6. Mutation of skin cells caused by exposure to UV rays.
A 7. Mutation on a recessive allele inherited from both parents
A 8. Mutation in a gamete

9. Sickle cell anemia is a genetic disease that affects the red blood cells. Your red blood cells are typically donut shaped and have the job of carrying oxygen around your body. In people with sickle cell anemia, the blood cells become crescent-shaped and are thick and sticky. They are not as able to carry oxygen, and can even get clogged in the blood vessels blocking the flow of blood, and therefore oxygen to organs, causing pain and organ damage.
Sickle cell is caused by a genetic mutation that changes a single glutamic acid to valine in the 6th amino acid position.
A) Examine the codon chart provided above (for #s 3-5), and determine what SINGLE POINT mutation likely occurred to cause the change from glutamic acid (GLU) to valine (VAL). To help get you started, it is helpful to know that a person with NO sickle cell at amino acid #6 has a DNA code of CTC. (4pts)
Normal RNA: ____________, Normal amino acid made: ___GLU________
Mutated RNA: ___________, Mutated amino acid made: ___VAL________

B) Your blood is a solution with water and blood cells.  Red blood cells contain a protein called hemoglobin.  Normally, hemoglobin is hydrophilic.  However, in a person with sickle cell anemia, the hemoglobin on the red blood cells forms long chains in an effort to avoid water.  These chains clump together, which results in the sickle shape of the cells. (Sickle Cell Disease) 

If Glutamic acid (GLU) is a polar, hydrophilic molecule, what would you suspect is different about Valine (VAL)? (3pts)

C) This mutation is a recessive trait. What is the likelihood that a woman who does not possess the sickle cell trait and a man who is a carrier of the sickle cell trait will have a child who suffers from sickle cell anemia? Explain your answer. (4pts)