The secondary structure is responsible for the shape that the nucleic acid assumes. The bases in the DNA are classified as purines and pyrimidines. ... A purine base always pairs with a pyrimidine base (guanine (G) pairs with cytosine (C) and adenine (A) pairs with thymine (T) or uracil (U)).
Is the letter D because your having half of their DNA. That's why your mother is contributing the Y chromosome and your father is contributing the X chromosome
Do you mean when nucleotides get damaged or when they match to each other incoreectly? (which cuases mutants) Specialized Enzymes repair, different one respond to help different types of damage. Detail the question more, maybe then i can help more.
The answer to your question is A., as the random movement is a movement