Biology U3 AOS1

• The sugar in DNA is deoxyribose, while the sugar in RNA is ribose.
• DNA has four bases (Adenine, Thymine, Cytosine, Guanine), while RNA has a different 4 bases (Adenine, Uracil, Cytosine, Guanine).
• DNA is a double stranded molecule in the form of a double helix
• RNA is single-stranded and does not have complementary base pairing like DNA.
• Hydrogen bonds hold the two strands of DNA together
• There are three types of RNA: mRNA, tRNA, rRNA
• Transcription is the process of copying the DNA into RNA, which is the first step in protein synthesis
• Translation is where the mRNA is decoded and the sequence of amino acids is read out
• tRNA's job is to carry amino acids to the ribosome
• codons are the sequence of three bases that code for an amino acid
• triplets are 3 bases that are repeated 3 times in a row
• a chromosome is a long coiled up DNA molecule that carries genetic information
• a gene is a section of DNA that codes for a specific protein.
• dysfunctional code is the idea that multiple codon groups can all code to the same amino acid
• mRNA is the messenger RNA that carries the genetic code from the nucleus to the ribosomes
• ribosomes are where proteins are made
• rRNA is a single stranded molecule that is a primary component of ribosomes
• Each nucleotide has three components:

  • A five-carbon sugar (Either ribose (RNA) or deoxyribose (DNA))
  • A negatively charged phosphate group
  • A nitrogenous base (Adenine, Guanine, Cytosine, Thymine (DNA) or Uracil (RNA))
• The complementary base pairing rule states that Adenine will always pair with Thymine (Uracil in RNA) and Guanine will always pair with Cytosine
• Protein synthesis involves transcription and translation.
• DNA will run 5' to 3' in one direction, and will run 3' to 5'. This is the antiparallel nature of DNA
• DNA is synthesised by the enzyme DNA polymerase
• RNA is synthesised by the enzyme RNA polymerase
• An intron is a sequence of DNA that is not translated into a protein.
• An exon is a sequence of DNA that codes for a protein.
• Amino acids are joined together by peptide bonds to form polypeptides.
• There are 20 different amino acids used in proteins.
• stop codons are the last three bases of a codon that code for a stop signal
• phosphodiester bonds are bonds between phosphate groups and deoxyribose sugar in the backbone of DNA
• the sugar phosphate backbone is made up of 2 deoxyribose sugar molecules and 1 phosphate group that are covalently bonded
• anticodons are complementary to the codons and are used to assemble amino acids
• the central dogma of biology is the idea that DNA is the genetic material that codes for the proteins that make up the cell
• RNA polymerase is a protein that catalyses the formation of RNA from DNA
• The non-template DNA strand is the strand that is complementary to the template strand - they will both have the same structure kind of thing
• the template strand of DNA is the strand that is the opposite of the produced RNA - it joins with the non template strand of DNA
• The genetic code is the same for all organisms - this is called 'universal'
• On average, each gene contains the coded instructions for

  making 40 proteins
• Once a polypeptide is synthesised, it may be:

  • methylated (CH3 – added)

  • acetylated (CH3CO – added)

  • phosphorylated (phosphate added)

  • glycosylated (sugar added)

  • lipidated (lipid added)
• Biomacromolecules are large organic molecules that are found in living organisms
• A carrier protein is a protein that can transport molecules across a membrane.