DNA and RNA Structure - AP Biology
- Identify the sugar found in DNA.
- Deoxyribose. Missing one hydroxyl group compared to RNA's ribose.
- What is the role of ligase in DNA replication?
- To join Okazaki fragments. Seals breaks between DNA fragments on lagging strand.
- Identify the type of RNA that forms the core of ribosome's structure.
- rRNA (ribosomal RNA). Structural component that catalyzes peptide bond formation.
- What is a codon?
- A three-nucleotide sequence in mRNA. Each triplet codes for one specific amino acid.
- Find the number of hydrogen bonds between Guanine and Cytosine.
- Three. G-C pairs are stronger than A-T pairs with two bonds.
- What is the role of tRNA in protein synthesis?
- To bring amino acids to ribosomes. Transfer molecules that deliver specific amino acids during translation.
- What is the start codon in mRNA sequences?
- AUG. Signals ribosome to begin protein synthesis.
- State the base pairing rule for DNA.
- A pairs with T, C pairs with G. Complementary base pairing ensures DNA stability and replication.
- What is the central dogma of molecular biology?
- DNA → RNA → Protein. Information flow from genes to functional proteins.
- Which enzyme is responsible for unwinding DNA during replication?
- Helicase. Breaks hydrogen bonds between base pairs to separate strands.
- What is the role of DNA polymerase?
- To synthesize new DNA strands. Adds nucleotides in 5' to 3' direction during replication.
- What is the template strand in DNA replication?
- The DNA strand used for mRNA synthesis. Serves as template for complementary RNA synthesis.
- Name the purine bases in DNA.
- Adenine and Guanine. Double-ring structures with nine-membered purine base.
- What is an intron?
- A non-coding region in mRNA. Removed during RNA processing before translation.
- Which base does cytosine pair with in DNA?
- Guanine. Forms three hydrogen bonds in complementary base pairing.
- Find the number of hydrogen bonds between Adenine and Thymine.
- Two. A-T pairs are weaker than G-C pairs with three bonds.
- What is the function of the promoter region in DNA?
- To initiate transcription. Binding site for RNA polymerase to start transcription.
- What is the primary function of DNA?
- To store genetic information. DNA contains hereditary instructions for all cellular processes.
- Which nucleic acid is single-stranded?
- RNA. Unlike DNA's double-stranded structure, RNA exists as single strand.
- Which process converts mRNA into a polypeptide chain?
- Translation. Second step where ribosomes decode mRNA into protein.
- What is the role of spliceosomes?
- To remove introns from mRNA. RNA-protein complexes that process pre-mRNA in eukaryotes.
- What is an exon?
- A coding region in mRNA. Remains in mature mRNA after splicing removes introns.
- Which enzyme synthesizes RNA from a DNA template?
- RNA polymerase. Reads DNA template strand to create complementary RNA.
- How many bases make up a codon?
- Three. Triplet code determines which amino acid is added.
- Which base does adenine pair with in RNA?
- Uracil. RNA uses uracil instead of thymine for adenine pairing.