In evolutionary terms, RNA is thought to have preceded proteins and DNA. Which of the following provides the most convincing support for this hypothesis?
a. there are more types of RNA than there are of DNA
b. RNA can both store genetic information and act as an enzyme
c. single stranded RNA is less structurally complex than double stranded DNA
d. viruses containing protein are among the oldest forms of life
B?
Yes, option B provides the most convincing support for the hypothesis that RNA preceded proteins and DNA in evolution.
To arrive at this answer, let's examine the options one by one:
a. While it is true that there are more types of RNA than DNA, this fact alone doesn't necessarily indicate that RNA preceded DNA evolutionarily.
b. This option states that RNA can both store genetic information and act as an enzyme. This is a critical point that supports the idea of RNA preceding proteins and DNA. The ability of RNA to store genetic information and also catalyze certain chemical reactions suggests that it could have served as both a genetic molecule and a functional molecule in early forms of life.
c. The statement that single-stranded RNA is less structurally complex than double-stranded DNA is true, but this fact alone does not provide evidence for the hypothesis that RNA preceded DNA evolutionarily. It merely highlights a structural difference between the two molecules.
d. This option suggests that viruses containing protein are among the oldest forms of life. However, it does not provide support for the hypothesis that RNA preceded proteins and DNA in evolution.
Therefore, option B is the most convincing support for the hypothesis that RNA preceded proteins and DNA in evolution, as it highlights the unique dual functionality of RNA as both a genetic molecule and an enzymatic molecule.