chapter 14. Mendel and the gene idea

chapter 14. Mendel and the gene idea

Q. what is the phenotypic percentage of f1 generation from two purple true-breeding parents ?

Q. why did Mendel choose pea plants for experiment?

Q. what is benefitial to use punnett square?

five facts

1. traits are transmitted from parents to offspring

2.

Mendel’s experiments succeeded because he counted so many offspring and was able to discern this statistical feature of inheritance and had a keen sense of the rules of chance.

3.

Mendel’s laws of independent assortment and segregation explain heritable variation in terms of alternative forms of genes that are passed along according to simple rule of probability.

4.

These laws apply not just to garden peas, but to all other diploid organisms that reproduce by sexual reproduction.

5.

Mendel’s law of segregation accounts for the 3:1 ratio that he observed in the F₂ generation.

key terms

1. character : a heritable feature that varies among individuals, such as flower color

2. true-breeding : such plants that had poduced only the same variety as the parent plant

3. hybridization : two true-breeding varieties

4. P generation : the true-breeding parents

5. F1 generation : first filial generation

6. F2 generation : second filial generation

7. alleles : alternative version of a gene

8. dominant allele : determines the organism's appearance

9. recessive allele : has no noticeable effect on the organism's appearance

10. law of segregation : the two alleles for a heritable character segregate (separate) during gamete formation and end up in different gametes

diagram

this diagram shows me the process of what Mendel had done to Pea plants. First he cut out the stamens from the purple flower in order to prevent self-polinating. Second he purposely moved sperm- bearing pollen from stamens forom white to egg-bearing carpel of purple. and he planted the result seeds. The result was all purple flowers appeared and he kept on doing the same process with the F1 generagion again.

video

http://www.youtube.com/watch?v=eOvMNOMRRm8&feature=related

summary

basically Mendel used the scientific approach to prove the two laws of inheritance which was the law of segregation and the law of independent assortment. He used detailed and a lot of information brought him to the father of genetic. the law of segregation is the two alleles for a character are packaged into separate gametes and the law of independent assortment is each pair of alleles segregates into gametes independently.