Inheritance and Evolution Mind Map

Inheritance, variation and evolution mind map · AQA GCSE Biology · clockitwithsci.com

Inheritance, variation and evolution

Reproduction
- Sexual vs asexual, meiosis
  - Gametes fuse, variety
  - One parent, clones
  - Meiosis halves chromosomes
  - Fertilisation restores number
- Pros and cons Triple only
  - Variation
  - Faster, one parent
  - Malaria, fungi, plants
- DNA and genome
  - Double helix
  - Gene codes for protein
  - Human genome uses
- DNA structure Triple only
  - Nucleotides: sugar, phosphate, base
  - Bases A, C, G, T
  - Three bases, one amino acid
- Protein synthesis and mutations Triple onlyHigher tier
  - C–G, T–A pairing
  - Ribosomes, carrier molecules
  - Mutation changes protein shape
  - Non-coding DNA switches genes
- Genetic inheritance
  - Alleles
  - Dominant, recessive
  - Punnett squares
  - Family trees
- Inherited disorders
  - Polydactyly
  - Cystic fibrosis
  - Embryo screening
- Sex determination
  - XX female
  - XY male
  - 1 : 1 ratio
Variation and evolution
- Variation
  - Genetic
  - Environmental
  - Both
- Mutations
  - Source of variants
  - Most no effect
  - Rare new phenotype
- Evolution
  - Natural selection
  - Survive and breed
  - New species
- Selective breeding
  - Choose parents
  - Many generations
  - Inbreeding
- Genetic engineering
  - Gene from another organism
  - GM crops
  - Human insulin
- Steps of genetic engineering Higher tier
  - Enzymes isolate gene
  - Vector: plasmid or virus
  - Insert into cells
- Cloning Triple only
  - Tissue culture
  - Cuttings
  - Embryo transplants
  - Adult cell cloning
Development of understanding
- Darwin Triple only
  - Observations
  - Origin of Species 1859
  - Gradual acceptance
- Lamarck Triple only
  - Inheritance of acquired changes
  - Rarely true
- Wallace and speciation Triple only
  - Joint writings 1858
  - Warning colouration
  - Steps to new species
- Mendel and genes Triple only
  - Units passed on
  - Chromosomes observed
  - DNA structure
- Evidence for evolution
  - Genes
  - Fossils
  - Antibiotic resistance
- Fossils
  - How formed
  - Record incomplete
- Extinction
  - New predators, diseases
  - New competitors
  - Environmental change
  - Catastrophic event
- Resistant bacteria
  - Mutation
  - Survive and reproduce
  - MRSA
  - Reduce misuse
Classification
- Linnaean system
  - Kingdom to species
  - Carl Linnaeus
- Binomial names
  - Genus
  - Species
- Three-domain system
  - Archaea
  - Bacteria
  - Eukaryota
- Evolutionary trees
  - Classification data
  - Fossil data
  - Common ancestors