Question

Name the scientists and write how did they explain Mendels laws after the chromosomes were discovered

Answer 1

Chromosomal theory

Explanation:

• Sutton and Boveri proposed the chromosomal theory of inheritance
• This theory states that individual genes are found at specific locations on particular chromosomes, and that the behavior of chromosomes during meiosis can explain why genes are inherited according to Mendel’s laws
• Observations that support the chromosomal theory of inheritance include:
• Chromosomes, like Mendel's genes, come in matched (homologous) pairs in an organism; for both genes and chromosomes, one member of the pair comes from the mother and one from the father
• The members of a homologous pair separate in meiosis, so each sperm or egg receives just one member, this process mirrors segregation of alleles into gametes in Mendel's law of segregation
• The members of different chromosome pairs are sorted into gametes independently of one another in meiosis, just like the alleles of different genes in Mendel's law of independent assortment
• Morgan chose the fruit fly, Drosophila melanogaster, for his genetic studies
• Morgan's crucial, chromosome theory-verifying experiments began when he found a mutation in a gene affecting fly eye color
• This mutation made a fly's eyes white, rather than their normal red
• Unexpectedly, Morgan found that the eye color gene was inherited in different patterns by male and female flies
• Male flies have an X and a Y chromosome (XY), while female flies have two X chromosomes (XX)
• Morgan realized that the eye color gene was being inherited in the same pattern as the X chromosome