Genetics

• Genetics

  • study of genes and heredity
• Gene

  • sequence of DNA that contains the information needed to make one protein
• Genome: 46 chromosomes --> genes: individual recipes --> alleles: versions of a recipe
• How to make protein

  1. DNA -> DNA
  2. Dna replication: making DNA out of DNA
  3. DNA -> RNA
  4. Transcription: making RNA out of DNA
  5. RNA -> Protein
  6. Translation: making protein out of RNA
• Mitosis

  • Cell division where the daughter cells are identical
  • Occurs in steps (IPMAT)
• Mitosis importance

  • all body cells remain identical, immune system won't attack
  • Repair damage, growth, reproduction
• Meiosis

  • cell division to make gametes
  • cells with only half of DNA
• Why sexual reproduction

  • Variation: every offspring is unique
  • if the environment changes in the future, some offspring may survive
• How to increase variation

  • random assortment
  • when you make gametes, one of each chromosome is placed inside
  • Crossover
  • in meiosis, chromosomes overlap and trade pieces of DNA
• DNA

  • Deoxyribonucleic acid
  • Polymer, made of monomers called nucleotides
• What is a nucleotide made of

  • Phosphate
  • sugar
  • nitrogenous bases
• the 4 nitrogenous bases

  • Guanine <-> Cytosine
  • Adenine <-> Thymine
• DNA Replication

  
• What enzymes aid with DNA replication

  1. DNA gyrase
  2. DNA helicase
  3. Single Stranded Binding Proteins
  4. RNA primer
  5. DNA polymerase 3
  6. DNA lygase
  7. DNA polymerase 1
• what are the functions of the following

  1. DNA gyrase: unwinds the strand
  2. DNA helicase: unzips the strand
  3. Single Stranded Binding Proteins: Attach to keep the strands apart for now
  4. RNA primer: Attaches and acts like a flag to tell DNA polymerase 1 where to begin
  5. DNA polymerase 3: attaches nucleotides to the 2 open strands (only works in direction 5 prime -> 3 prime)
  6. DNA ligase: stitches together ozaki fragments
  7. DNA polymerase 1: fixes errors
• How does DNA polymerase 3 work

  • One strand built easily, leading strand
  • One strand built backwards in fragments, lagging strand
  • Fragments are called ozaki fragments
• • DNA contains the code/instructions to make proteins
  • Protein makes up 60% of your dry weight and does pretty much anything
  • DNA makes RNA which carries instructions out to ribosomes which are protein factories
• "cast" of protein synthesis

  • DNA
  • RNA
  • 3 kinds
  • mRNA, messengers, carries DNA to ribosomes
  • tRNA, transfer, acceptor end where amino acids attach, anticodon, attaches to mRNA
  • rRNA, ribosomal, makes up ribosomes with protein
  • Protein, made of amino acids put together in the correct order
• • Incomplete dominance: a situation where neither alleles are dominant, a blending of traits
  • Codominant, a situation where both alleles are dominant, both show up in the phenotype
• Multiple alleles

  • Individuals can only have up to 2 alleles but there can be more than that in a species or population
  • EG, blood types
  • A - A protein on blood surface
  • B - B protein on blood surface
  • O - no protein on blood surface
• X-linked dominant trait

  A trait influenced by a dominant allele on the X chromosome; affected females are typically carriers, while affected males have only one X chromosome