Genbio

• Genetics


  The science that deals with the heredity and the factors that affect the transmission of traits from one generation to another
• Heredity


  The transmission of genetic materials from the parents to offspring
• Factors of heredity


  • Biological factor
  • Environment
  • Advanced technology
• Gene


  The factor that control the inheritance that is responsible for the transmission of traits
• Gregor Mendel was an Augustinian monk in Brunn, Austria and was known as the Father of Classical Genetics
• Blending theory of inheritance

  The inheritance of traits from two parents produces offspring with characteristics that are intermediate between those of the parents
• Mendel disproved the blending theory of inheritance because when he cross pollinated tall pea plants and short pea plants, the resulting offspring were either tall or short, not medium like what the blending theory suggests
• Why Mendel chose pea plants

  • Easy to cultivate
  • Perfect flower
  • Cross pollination can be done manually
  • Short generation time
  • With pair of contrasting traits
• Mendel's experiment was on seven contrasting traits of pea plants
• Principle of dominance


  In each organism, there is a pair of factors which controls the appearance of a particular trait. One member of the pair of factors may hide or prevent the appearance of the other factor.
• Dominant trait


  Usually seen or expressed, symbolized by capital letters
• Recessive trait


  Usually hidden or not expressed, symbolized by small letters
• Homozygous (pure-bred)


  The gene pairs are identical
• Homozygous dominant

  The gene pairs are both dominant, symbolized by both capital letters
• Homozygous recessive


  The gene pairs are both recessive, symbolized by both small letters
• Heterozygous (hybrid)


  The gene pairs are not identical, symbolized by one capital letter and one small letter
• Alleles


  The alternative forms of genes
• Phenotype


  The physical appearance of an organism usually an adjective or words describing a trait
• Genotype


  The genetic make-up of an organism usually a letter symbolizing the trait of an organism
• Mendel's laws of inheritance were derived from his hybridization experiments in garden peas between 1856 and 1863
• Mendel's law of segregation


  When two traits come together in one hybrid pair, the two characters do not mix with each other and are independent of each other. Each gamete receives one of the two alleles during meiosis of the chromosome.
• Mendel's law of segregation supports the phenotypic ratio of 3:1 i.e. the homozygous dominant and heterozygous offspring show dominant traits while the homozygous recessive shows the recessive trait
• The gametes have two versions of each chromosome: one contributed by the female parent in her ovum and one by the male parent in his sperm. These are joined at fertilization. The ovum and sperm cells (the gametes) have only one copy of each chromosome and are described as haploid
• Mendel's law of dominance

  In a heterozygous condition, the allele whose characters are expressed over the other allele is called the dominant allele and the characters of this dominant allele are called dominant characters. The characters that appear in the F1 generation are called dominant characters, and the recessive characters appear in the F2 generation.
• What is the scientific name of pea plants

  Pisum sativum
• Mendel's law of independent assortment/dihybrid cross

  At the time of gamete formation, the two genes segregate independently of each other as well as of other traits.
• Reginald Punnett became interested in the experimental process during his stay at Cambridge and began a scientific collaboration with William Bateson, who was doing Mendelian experimentation on plants and animals. They both published the first account of gene linkage in sweet peas and later developed the "Punnett square".
• Punnett square


  A tool used to predict the possible breeding outcomes of two genes that segregate independently of each other as well as of other traits.

  
• How many pea plants did mendel use for his expirement

  28,000
• how many years did mendel experiment the pea plants?

  7 years
• DNA also called____


  blue print of life
• Chromosome is located at?

  Nucleus
• Hidden traits called?

  recessive traints
• showing traits called?


  dominant traits
• give the 7 genetics term to remember :

  1. Dominant Trait

  2.Recessive trait

  3.homozygous (pure bread )

  4. heterozygous (hybrid)

  5. Allele

  6. Phenotype

  7. Genotype
• Who found out that inherited trait is determined by a chromosome and the coin word gene

  Walter sutton and theodori boveri