Which one is false which one is true , if its false put the right sentence?

a. Ribosomes move along mRNA in a 5' ---%26gt; 3' direction. -----------------


b. the genetic change responsible for the disease sickle cell anemia is a point mutation. ------------------





c. the mRNA transcript of a gene is made up of the same bases, in the same proportion, as the strand of DNA complementary to the template strand, except the uracil will be replaced by the thymine. ------------------------


d. the fact that the genetic code is very different in almost all organisms indicates that it evolved early in the history of life on earth. -------------------------

Which one is false which one is true , if its false put the right sentence?
A is true.


B. is true. The point mutation is the sostitution of the nucleotide A with T. This cause the sostitution of Glu with Val in the polypeptide.


C is true (but the mRNA does not have already undergone the process of splicing)


D is false. The genetic code is common in almost all organism. It evolved early in the history of life, but it has been conserved.