Even in the absence of genetic recombination, meiosis is an important source of genetic variation in sexually reproducing organisms. Use as an example a species with 2n=8, and an individual of that species that is a quadruple heterozygote for loci A, B, C, and D, with each loci on a different chromosome. Determine how many different types of gametes this individual can produce, and explain how segregation and independent assortment mechanisms produce genetic variation in the gametes produced by this individual. Use the following terms in your response: genes; alleles; homologous chromosomes; non-homologous chromosomes

Because of non-disjunction in some stocks of Drosophila. melanogaster, about 1 in 65,000 egg cells have two copies of the X chromosome and about 1 in 375 egg cells have no X chromosome. Assuming that meiosis in males is ‘always normal', what is the expected frequency of XXX females and XO males arising from any number of fertilized eggs? Do not be concerned as to whether it is lethal or not.

Explain why heterozygotes for inversions and translocations have low fertility.

Assume that D, E, F, G, H, and I are autosomal genes on different chromosomes. From the mating (parent A) Dd ee Ff GG Hh li x (parent B) Dd EE FF Gg Hh ii. A. What is the probability that one of the offspring will have the genotype Dd Ee FF Gg hh li? B. What is the probability that one of the offspring will be heterozygous for each allele?

What will be the number of chromosomes in Turner’s syndrome and Klinefelter's syndrome of an organism whose haploid number is 20

In fruit flies, chromosomal crossing over does not occur in meiosis in males, whereas crossing over does occur in meiosis in females. In fruit flies that are heterozygous at many genes (i.e. many maternal and paternal versions of the genes differ), at what stage would cells no longer be heterozygous for any gene during the process of meiosis? a)After the second meiotic division in males, and after the first meiotic division in females. b)After the second meiotic division in both males and females. c)After the first meiotic division in both males and females. d)After the first meiotic division in males, and after the second meiotic division in females.

How do you determine the amount of DNA picograms for each stage in Meiosis? (for a cell 2n=4 for reference)