Question
Which processes are involved in the development of cancer?
Mutations occur in oncogenes.
Oncogenes prevent cancer.
Oncogenes affect cell cycle regulatory proteins.
I and II only
I and III only
II and III only
I, II and III
Answer/Explanation
Ans: B
In a person who is heterozygous for sickle-cell anemia, where is the mutation found?
A. In every gamete produced
B. Only in gametes carrying an X chromosome
C. In all brain cells
D. In blood plasma
Answer/Explanation
Markscheme
C
One type of gene mutation involves a base substitution.
What are the consequences of the base substitutions in the two new sequences of DNA?
A. Both are mutations that would result in different polypeptides.
B. Sequence 2 would result in a changed polypeptide but sequence 1 would not.
C. All three DNA sequences would translate into the same polypeptide.
D. Only the original DNA and sequence 2 would translate into the same polypeptide.
Answer/Explanation
Markscheme
D