Question

which of the following changes in a cga codon would change the primary structure of a protein? a mutation that replaces the c with an a. a mutation that replaces the a with a g. a mutation that replaces the g with an a. any of the mutations listed will change the primary structure of the protein.

Explanation:

The CGA codon codes for arginine. Changing the first - letter C to A gives AGA which also codes for arginine. Changing the third - letter A to G gives CGG which also codes for arginine. But changing the second - letter G to A gives CAA which codes for glutamine. A change in the amino - acid sequence (due to a codon change resulting in a different amino - acid) changes the primary structure of a protein.

Answer:

A mutation that replaces the G with an A