DNA, Transcription, Translation

DNA

•  What does DNA stand for?

  • DeoxyriboNucleic Acid

•  What subunit is DNA made up of?

  • Nucleotides

• What makes up a DNA nucleotide?

  • 3 Parts

    • Phosphate

    • Pentose Sugar - Deoxyribose (sugar)

    • Nitrogenous Base (A,T,G,C)

•  What are the nitrogenous bases?

  • Adenine (A)

  • Thymine (T)

  • Guanine (G)

  • Cytosine (C)

•  What are the base pairing rules?

  • Adenine (A) → Thymine (T)

  • Guanine (G) → Cytosine (C)

•  What is the structure of a DNA molecule? 

  • Double Helix. They are two complementary strands; each made of a sequence of nucleotides.

•  What happens during the process of DNA replication?

  • During the process of DNA replication

DNA Replication

• What proteins (enzymes) are used in DNA replication? What is the function of each of them?

• Where does DNA replication occur?

• Given the following DNA code, can you identify the code on the other strand of the DNA? TACCTAGCCAGTCGG

  • ATGGATCGGTCAGCC

• Why is DNA replication necessary? 

RNA

• What is RNA?

  • Ribonucleic acid (RNA) is a molecule that is present in the majority of living organisms and viruses. It is made up of nucleotides, which are ribose sugars attached to nitrogenous bases and phosphate groups 

• What subunit is RNA made up of?

  • A nucleotide is the basic building block of nucleic acids (RNA and DNA). A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base. The bases used in DNA are adenine (A), cytosine (C), guanine (G) and thymine (T).

• What are the nitrogenous bases? 

  • Adenine (A)

  • Thymine (T)

  • Guanine (G)

  • Cytosine (C)

• What are the differences between RNA and DNA?

  • RNA is single-stranded, while DNA is double-stranded.

  • RNA contains ribose sugar, whereas DNA contains deoxyribose sugar.

  • RNA uses uracil (U) in place of thymine (T).

  • RNA is more involved in protein synthesis, while DNA stores genetic information.

• What are the types of RNA? What does each type do?

  • mRNA (messenger RNA): Carries the genetic code from DNA to the ribosome for protein synthesis.

  • tRNA (transfer RNA): Delivers amino acids to the ribosome based on the codons in mRNA.

  • rRNA (ribosomal RNA): Combines with proteins to form ribosomes, which facilitate protein assembly.

Transcription

• What are the processes involved in transcription?

  • Initiation: RNA polymerase binds to the DNA at the promoter region.

  • Elongation: RNA polymerase synthesizes the mRNA strand complementary to the DNA template.

  • Termination: Transcription stops when the polymerase reaches a termination signal.

• Where does transcription occur?

  • In the nucleus of eukaryotic cells

• What are codons?

  • Codons are three-nucleotide sequences on mRNA that specify a particular amino acid, a stop signal, or a start signal during protein synthesis.

• What is the start codon?

  • The start codon is AUG, which codes for methionine.

• Can you read the codon chart correctly?

• Given the following DNA code, can you identify the code on the mRNA

• strand? TACCTAGCCAGTCGG

  • AUGGAUCGGUCAGCC

Translation

• What are the processes involved in translation?

  • Initiation: The ribosome assembles around the mRNA and the start codon (AUG).

  • Elongation: tRNA brings amino acids to the ribosome, which are added to the growing polypeptide chain.

  • Termination: Translation ends when a stop codon (UAA, UAG, or UGA) is reached.

• Where does translation occur?

  • On ribosomes inside of a cell’s cytoplasm

• Can you translate an mRNA into an amino acid sequence?

  • Yes, using the codon chart.

• Using the mRNA sequence from transcription, translate it into the amino acid sequence. 

  • mRNA Sequence: AUGGAUCGGUCAGCC

  • Amino Acid Sequence: Methionine, Aspartic Acid, Arginine, Serine, Alanine

• What are anticodons?

  • Anticodons are three-nucleotide sequences on tRNA that are complementary to codons on mRNA, ensuring accurate amino acid delivery during translation.