Inheritance and Variation

Inheritance and Variation

1. Two types of variation

   • Discontinuous
     • Genetic
       • Passed on from parents
         • INHERITED
   • Continuous

2. Genetic information is passed on by parents to their offspring

   • This information can be beneficial or not
     • Sometimes the information leads to illnesses such as Cystic Fibrosis
       • This is known as a genetic disorder
     • Beneficial information is something that would allow the offspring to survive better than other organisms in an environment
       • Examples of this are shown in the picture of the polar bear
       • These are commonly called ADAPTATIONS
         • If an organism has a more effective adaptation than another it will help it to survive and reporduce
           • This is the basis of EVOLUTION and is called THE SURVIVAL OF THE FITTEST
     • Both of these are discontinuous variation

3. Genetic information is stored in the GENES which are small parts of CHROMOSOMES found in the NUCLEUS of the cell

   • Characteristics of an organism can be determined if gene types are known. Different types of the same GENE are called ALLELES
     • Alleles are DOMINANT OR RECCESIVE. The dominant allele gets its name because it appears in the characteristic. It is exactly the same as the recessive one.
       • Characteristics can be determined using punnett diagrams
         • or Pedigree Diagrams
           • The characteristics are called PHENOTYPES
         • Allele types CC or Cc are galled GENOTYPES
           • This diagram shows 50% CC 50% Cc
             • This one 25%, 50%, 25%

Images and files in the map