genetics

• sexual reproduction


  fusion of male and female gametes
• asexual reproduction


  requires only one parent without the mixing of genetic material
• benefits of asexual reproduction


  • only one parent is needed
  • this speeds up the process
• disadvantages of asexual reproduction


  • no genetic variation , so population could be wiped out
  • less chance of adapting to a new condition
• benefits of sexual reproduction

  • lots of genetic variation
  • less likely to get wiped out
  • allows evolution
• disadvantages of sexual reproduction


  • takes more time and energy
  • you need to impress you mate
• how does meiosis work


  • replicate cells DNA
  • line up along the centre of the cell with their pairs
  • chromosomes are pulled apart and randomly distributed
  • line up at the cell again and the arms of the chromosomes are pulled apart
  • divided again
• what is transcription


  process of taking a single gene of Dna and copying it into mRNA
• translation


  copies mRNA and then makes it into a protein
• transcription?

  • Rna polymerase attaches to noncoding part of the DNA
  • Rna polymerase seperates two strands of dna to access the bases
  • Rna polymerase then makes mRNA by linking two bases which are complimentary to the DNA
  • mRNA travels out of the nucleus through a nuclear pore
• translation

  • a ribosome attaches to mRNA
  • a ribosome moves along the mRNA and reads each codon
  • tRNA molecule pairs with triplet mRNA codon
  • ribosome join amino acids carried by the tRNA
  • forms a polypeptide , protien folds into shape
• gregor mendel

  • did experiments on peas
  • found out that some genes were dominant and some ressesive