Many years ago in Kew Gardens in London, two ornamental primrose plants were cro
ID: 202100 • Letter: M
Question
Many years ago in Kew Gardens in London, two ornamental primrose plants were crossed. The two plants were from different species, Primula verticillata and P. floribunda, both normal diploids. This cross produced a vigorous hybrid that was sterile, but which could be propagated vegetatively by cuttings. After many such propagations, the hybrid yielded a branch that bore fertile seeds. The plants that developed from these seeds were named Primula kewensis.
a. In one or two sentences explain why the original hybrid was sterile.
b. In one or two sentences explain what happened for production of fertile seeds.
c. Primula kewensis is which option below:
i. Autodiploid ii. Allodiploid iii. Autotriploid iv. Allotriploid v. Autotetraploid vi. Allotetraploid
d. If the original parents, P. verticillata and P. floribunda, each produce haploid gametes containing 9 chromosomes, how many chromosomes are present in P. kewensis?
e. How many bivalents would you expect to see during the first meiotic prophase in P. kewensis?
Explanation / Answer
A. They are from different species they dont have exact pair of chromosome in the hybrid. So, during meosis
the chromosome segregation has a problem
B. There is some abnormal division occurs in the cell division it brings down the pair of chromosomes and create the gametes.
C. Allotetraploid
D. 36 chromosomes
E. 18 bivalents