🔬biological chemistry i review
key term - Nitrogenous bases
Definition
Nitrogenous bases are the fundamental building blocks of nucleic acids like DNA and RNA, consisting of nitrogen-containing molecules that play a crucial role in storing and transmitting genetic information. They pair specifically to form the rungs of the nucleic acid ladder, contributing to the overall structure of RNA and influencing its various functions and types.
5 Must Know Facts For Your Next Test
- There are five primary nitrogenous bases: adenine (A), guanine (G), cytosine (C), uracil (U) in RNA, and thymine (T) in DNA.
- In RNA, adenine pairs with uracil instead of thymine, which is found in DNA, making RNA structurally unique.
- Nitrogenous bases are classified into two categories: purines (adenine and guanine) and pyrimidines (cytosine, uracil, and thymine).
- The sequence of nitrogenous bases along the RNA strand encodes genetic information, guiding protein synthesis through processes like transcription and translation.
- Mutations in the sequence of nitrogenous bases can lead to changes in protein function, potentially resulting in various genetic disorders or diseases.
Review Questions
- How do nitrogenous bases contribute to the structure and function of RNA?
- Nitrogenous bases are essential for the structure of RNA as they form base pairs that stabilize the molecule. In RNA, adenine pairs with uracil, while cytosine pairs with guanine. This base pairing not only contributes to the overall three-dimensional shape of RNA but also facilitates the encoding of genetic information necessary for protein synthesis.
- Compare the roles of nitrogenous bases in DNA and RNA, highlighting key differences.
- In DNA, nitrogenous bases include adenine, thymine, cytosine, and guanine, while in RNA, they consist of adenine, uracil, cytosine, and guanine. One major difference is that DNA uses thymine instead of uracil. This distinction affects how genetic information is stored and transferred; DNA serves as a long-term storage medium for genetic info, while RNA plays a more active role in protein synthesis and regulation.
- Evaluate how changes in the sequence of nitrogenous bases can affect genetic expression and lead to disease.
- Changes in the sequence of nitrogenous bases can result in mutations that alter the amino acid sequence of proteins synthesized from mRNA. These alterations may lead to misfolded proteins or nonfunctional proteins that disrupt normal cellular processes. Such mutations can be benign or result in diseases such as cancer or genetic disorders depending on their impact on gene function and expression regulation.