Biology

• Meiosis is the process by which sex cells (gametes) are produced through cell division.
• • gene - A study of genes, heredity, and variation.
• Heredity


  The transmission of traits from parents to offspring.
• Variation

  • The difference existing between individuals of the same species
• • The unit of heredity found on the chromosome


  gene
• • Both sexes contribute equally to an individual

  Blending Theory of inheritance
• Gregor Johann Mendel

  • Austrian-Agustinian monk and the “Father of Modern Genetics”
• Pisum Sativum


  22pcs. of Garden Pea that mendel used in his study
• Cross Pollination

  • he process of applying pollen from one flower to the pistils of another flower that mendel used in his experiment.
• Seed shape, color, and flower color

  • The inheritance of relatively distinguishable traits that mendel observed.
• • Each organism contains 2 factors of each trait, the factors segregate (separate) during the meiosis cell division so that each gametes contain only one factor for each trait. When the fertilization occurs the new organism has 2 factors for each trait, one from each parent.


  Law of Segregation
• Law of Independent Assortment

  • Members of one pair of factors segregate (assort) independently from members of another pair of factors. Therefore all possible combinations of factors can occur in the gametes.
• Law of Dominance

  • The first generation shows only one trait the dominant trait and the other trait that is hidden is the recessive trait. In heterozygous trait, the dominant trait is expressed. The recessive trait appears when it is paired with another recessive trait.   
• Locus


  he location of the gene in the chromosome
• Genes 


  • The molecules of the DNA that determines the trait of the offspring it contains the code for RNA for protein synthesis.
• Allele

  • Alternating pair of similar or contrasting characters of a gene
• Homozygous

  • A pair of identical alleles (Pure breed)
• Heterozygous

  • A pair of different alleles (Hybrid)
• LOH (Lost of heterozygosity)

  • the loss of one parent's contribution to the cell
• Chromosome

  • Rod-shaped body in the nucleus that contains the hereditary trait.
• Dominant Trait

  • The stronger and fully expressed allele, it shows in heterozygous phenotype
• Recessive Trait

  • The weaker allele, it requires another recessive allele to show.
• • An organism who has a “True nucleus”

  Eukaryotes
• • An organism who has no nucleus

  Prokaryotes
• • An extra copy of chromosome


  Trisomy
• Aberration

  • Abnormality in the chromosome
• Karyotyping

  • a test to examine chromosomes in a sample of cells. This test can help identify genetic problems as the cause of a disorder or disease
• Cell -> Nucleus -> Chromosome -> Gene -> DNA -> Nucleotide
• Hybrid

  • An offspring of 2 parent that differ in inheritable character
• Genotype

  • The genetic code or makeup of an organism in other words, it describes an organism's complete set of genes. 
• Phenotype

  • The set of observable characteristics of an individual; the physical characteristics of an organism.
• Test Cross

  • A test to determines if an individual is Heterozygous or Homozygous
• Monohybrid Cross

  • A cross of only 1 pair of gene
• Dihybrid Cross

  • A cross of 2 pairs of gene
• Punnet Square


  A test used to determined the probable genotype and phenotype produced
• Pedigree Analysis

  • An analysis to determine the inheritance and probability of an offspring to be affected; a chart that can represent a family tree along with the family members and their genetic traits, respectively.
• Sex Limited Traits

  • Autosome found in both sexes but the trait is only for one sex 
  • The characters are limited only to one sex due to hormone
  • Ex: Beard and milk production
• Sex Influence Traits

  • Traits that act differently in male or female
  • Autosomal Traits are influence by sex 
  • Ex: Baldness
• Sex Linked Traits

  • A trait is controlled by its presence on the sex chromosome
  • Ex: hemophilia, color blindness
• Replication of DNA

  • The process of copying DNA molecule