lab three mitosis and meiosis. 3a.1 observing mitosis 3a.2 time for cell replication 3b.1 simulation...

LAB THREE Mitosis and Meiosis

3A.1 Observing Mitosis

3A.2 Time for Cell Replication

3B.1 Simulation of Meiosis

3B.2 Crossing Over During Meiosis


EXERCISE 3B.2: Crossing over during Meiosis in Sordaria



Number of 4:4

Number of Asci

Showing Crossover

Total Asci % Asci Showing

Crossover Divided by 2

Gene to Centromere

Distance (map units)



Why do we divide the % by 2?



Crossing over happened between these two chromatids…




…but not between these two




…but not between these two

so it only happened ½ the time.



A map unit is equal to the % of time that crossover happens between two genes or between a gene and the centromere.



Map units show us relative distances between genes



Map units show us relative distances between genes.

They do not translate directly into numbers of nucleotide pairs




They do not translate directly into numbers of nucleotide pairs.

Genes that are more than 50 map units apart assort independently…




They do not translate directly into numbers of nucleotide pairs.

Genes that are more than 50 map units apart assort independently… and might as well be on separate chromosomes.


lab three mitosis and meiosis. 3a.1 observing mitosis 3a.2 time for cell replication 3b.1 simulation...

Documents

meiosis slide

meiosis lab

simulation of meiosis

sordaria lab

sordaria crossing

genes lab

chromatids lab

sordaria map units