The nucleic acids DNA and RNA are made of repeating units called?
The correct answer and explanation is:
Correct Answer:
The nucleic acids DNA and RNA are made of repeating units called nucleotides.
Explanation (300 words):
Nucleic acids, which include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), are essential biomolecules that store and transmit genetic information in all living organisms. The fundamental building blocks of both DNA and RNA are nucleotides.
Each nucleotide is composed of three parts:
- A phosphate group
- A five-carbon sugar
- Deoxyribose in DNA
- Ribose in RNA
- A nitrogenous base
- DNA uses adenine (A), thymine (T), cytosine (C), and guanine (G)
- RNA uses adenine (A), uracil (U), cytosine (C), and guanine (G)
Nucleotides link together through phosphodiester bonds, forming a long chain or polymer. This repeated linkage gives DNA and RNA their characteristic backbone structure. In DNA, the double helix is formed when two strands of nucleotides pair through complementary base pairing (A with T, and C with G), stabilized by hydrogen bonds. RNA typically exists as a single strand but can form complex secondary structures by folding upon itself.
These nucleotide chains carry the genetic instructions necessary for life. In DNA, the specific sequence of nucleotides forms genes, which provide the blueprint for proteins. RNA plays various roles, including carrying instructions from DNA (messenger RNA or mRNA), forming part of the ribosome (ribosomal RNA or rRNA), and helping in protein synthesis (transfer RNA or tRNA).
In summary, nucleotides are the basic units that repeat to form DNA and RNA. They are essential for storing genetic information, enabling heredity, and guiding cellular function through protein synthesis. Without nucleotides, the processes of inheritance, growth, and development would not be possible.