BRAINCAKEDNA, Genes and Protein Synthesis
Revision notes for DNA, Genes and Protein Synthesis in Edexcel Biology B (8BI0). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- NucleotidesNucleotides are the monomers that make up the nucleic acids DNA and RNA.
- ATPATP (adenosine triphosphate) is the immediate source of energy in all cells.
- Nucleic AcidsThe nucleic acids, DNA and RNA, are polymers of nucleotides, so they are called polynucleotides.
- Phosphodiester BondsNucleotides are joined into a polynucleotide chain by phosphodiester bonds.
- Complementary Base PairingThe two strands of a DNA double helix are held together by hydrogen bonds between the bases.
- Evidence for Semi-Conservative DNA ReplicationWhen Watson and Crick described DNA, three ways of copying it were possible: • conservative: the original molecule stays intact and a completely new…
- DNA ReplicationDNA is copied before a cell divides, during interphase, so that each daughter cell receives an identical copy.
- The Genetic CodeThe genetic code is the set of rules by which the base sequence of DNA (and mRNA) is converted into the amino acid sequence of a polypeptide.
- Types of RNARNA (ribonucleic acid) is a polynucleotide made of nucleotides containing ribose, a phosphate group and one of the bases A, U, C or G.
- mRNAMessenger RNA (mRNA) carries the genetic information of a gene from DNA, which stays in the nucleus, to the ribosomes in the cytoplasm where the…
- tRNATransfer RNA (tRNA) brings amino acids to the ribosome in the correct order during translation.
- rRNARibosomal RNA (rRNA) is the most abundant type of RNA in a cell.
- Protein SynthesisA gene is a sequence of bases on a DNA molecule that codes for the sequence of amino acids in a polypeptide.
- TranscriptionTranscription is the first stage of protein synthesis: a gene's base sequence is copied into mRNA.
- TranslationTranslation is the second stage of protein synthesis: the mRNA base sequence is used to make a polypeptide with a specific amino acid sequence.
- PolysomesA single mRNA molecule does not have to be translated by just one ribosome at a time.
- MutationsA mutation is a change in the genetic material of a cell.
- Gene MutationA gene mutation (point mutation) changes one or a few bases in the DNA of a gene.
- Sickle Cell DiseaseSickle cell disease is an inherited disorder caused by a single base substitution in the gene for the β-globin chain of haemoglobin.
- Chromosome MutationsChromosome mutations affect large sections of DNA or whole chromosomes, so they usually change many genes at once.
On the specification
- 1.4 DNA and protein synthesis