Skip to main content
Indietro

General Biology: Nucleic Acids and RNA World

I pulsanti di controllo sono stati cambiati in modalità "navigazione".
1/20

Termini in questo insieme (20)

  • What are the three components of a nucleotide?

    Phosphate group, five-carbon sugar, and nitrogenous base.

  • What is the difference between ribonucleotides and deoxyribonucleotides?

    Ribonucleotides contain ribose sugar, while deoxyribonucleotides contain deoxyribose sugar (lacking one oxygen atom).

  • Which nitrogenous bases are purines and which are pyrimidines?

    Purines: Adenine and Guanine (double-ring structures). Pyrimidines: Thymine, Cytosine, and Uracil (single-ring structures).

  • How do nucleotides polymerize to form nucleic acids?

    Via phosphodiester linkages formed by condensation reactions between the sugar's hydroxyl group and the phosphate group, releasing water.

  • What is the directionality of DNA and RNA strands?

    Strands are read from the unlinked 5’ phosphate end to the unlinked 3’ hydroxyl end.

  • How does adding phosphate groups raise the potential energy of nucleotides?

    Phosphates are negatively charged; linking them creates covalent bonds with high potential energy due to repulsive forces, releasing energy when forming stable bonds.

  • What did Rosalind Franklin and Maurice Wilkins discover about DNA structure?

    Using X-ray crystallography, they found DNA has a helical and regular repeating structure.

  • Describe the secondary structure of DNA.

    Two antiparallel strands twisted into a double helix, stabilized by hydrogen bonds between complementary base pairs and van der Waals interactions.

  • How is DNA compacted inside cells?

    DNA undergoes supercoiling and forms chromatin to compact into discrete, movable units.

  • What is the primary function of DNA's primary structure?

    Serves as a template for DNA replication by allowing strands to separate and complementary strands to form.

  • What sugar is present in RNA and how does it differ from DNA sugar?

    RNA contains ribose, which has one more oxygen atom than DNA's deoxyribose.

  • Which pyrimidine base is unique to RNA?

    Uracil replaces thymine in RNA.

  • How does RNA secondary structure differ from DNA?

    RNA forms hydrogen bonds within the same strand, creating structures like hairpins, rather than between two strands.

  • What is RNA tertiary structure?

    Complex 3D shapes formed when secondary structures fold further, such as pseudoknots.

  • What is the role of messenger RNA (mRNA)?

    Transmits genetic information from DNA to synthesize polypeptides (proteins).

  • What are ribozymes?

    RNA molecules that can catalyze chemical reactions, similar to protein enzymes.

  • How does RNA replication occur?

    A complementary RNA strand forms using the original as a template, linking ribonucleotides via phosphodiester bonds.

  • What is the Central Dogma of molecular biology?

    Describes the flow of genetic information: DNA replicates, transcribes to RNA, which translates to protein.

  • What stabilizes the DNA double helix structure?

    Hydrogen bonds between complementary bases, hydrophobic interactions, and van der Waals forces stabilize the helix.

  • What is the significance of antiparallel strands in DNA?

    One strand runs 5’ to 3’, the other 3’ to 5’, allowing complementary base pairing and proper double helix formation.