Multiple Choice
If DNA is described as a double helix, how should mRNA be described?
3
views
7. DNA and Chromosome Structure
RNA
Struggling with Genetics?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Which of the following best explains why RNA molecules are generally smaller than DNA molecules?
A
RNA is composed of ribose sugars, which are smaller than the deoxyribose sugars in DNA.
B
RNA contains uracil instead of thymine, which makes its molecules physically smaller.
C
RNA is found only in the cytoplasm, where smaller molecules are required.
D
RNA is typically single-stranded and shorter because it serves as a temporary copy of genetic information, while DNA is double-stranded and stores the entire genome.
Verified step by step guidance1
Understand the structural differences between RNA and DNA molecules, focusing on strand number and length.
Recall that DNA is typically double-stranded and contains the entire genetic information of an organism, making it very long.
Recognize that RNA is usually single-stranded and functions as a temporary copy or messenger of specific genes, so it is shorter.
Consider that the sugar type (ribose in RNA vs. deoxyribose in DNA) and base differences (uracil vs. thymine) do not significantly affect the overall size of the molecules compared to strand number and length.
Conclude that the main reason RNA molecules are generally smaller than DNA molecules is due to their single-stranded nature and their role as temporary, shorter copies of genetic information.
Related Videos
Related Practice
