Presentation is loading. Please wait.

Presentation is loading. Please wait.

Genetics.

Similar presentations


Presentation on theme: "Genetics."— Presentation transcript:

1 Genetics

2 Heredity and Genetics Gregor Mendel studied thousands of pea plants to up with the basic principles of heredity that we still use today

3 Heredity and Genetics These principles all start with sexual reproduction – where two prents combine sex cells (each with ½ of their DNA) to create new organisms - now with a combination of traits from each parent

4 Heredity and Genetics Chromosomes are coiled pieces of DNA and protein that carry genes (which code for a specific trait). Each form of a gene is called an allele. Alleles can be dominant or recessive.

5 Heredity and Genetics Dominant alleles will always present – or show (RR or Rr), while a recessive trait will only show itself if two recessive alleles are present (rr).

6 Heredity and Genetics An organism’s geneotype is represented by the letters – RR, Rr, or rr. The phenotype for these genotypes is either round or wrinkled.

7 Heredity and Genetics Reginald Punnett developed a tool called the Punnett Square – it is a way to predict all of the possible genotypes offspring could have. Each box in the Punnett Square shows a way the alleles from each parent could combine in potential offspring.


Download ppt "Genetics."

Similar presentations


Ads by Google