In flies one gene controls body color gray or yellow and ano

In flies, one gene controls body color (gray or yellow), and another gene controls wing length (short or long). A pure-breeding gray, short-winged female mates with a pure-breeding yellow, long-winged fly. All progeny are gray with long wings. One of the F1 females is crossed to a male that is homozygous recessive for both genes, and produces the following offspring. Do these data support inheritance by classic Mendelian patterns? How far apart are the two loci?

Solution

Yes, above data support inheritance of Mendelian patterns.

As per Mendelian law allele pairs separate randomly, or segregate, from each other during the production of gametes( offspring)Because allele pairs separate during gamete production, a sperm or egg carries only one allele for each inherited trait. When sperm and egg unite at fertilization, each contributes its allele, restoring the paired condition in the offspring. This is called the Law of Segregation. Mendel also found that each pair of alleles segregates independently of the other pairs of alleles during gamete formation. This is known as the Law of Independent Assortment.

The genotype of an individual is made up of the many alleles it possesses. An individual\'s physical appearance, or phenotype, is determined by its alleles as well as by its environment. The presence of an allele does not mean that the trait will be expressed in the individual that possesses it. If the two alleles of an inherited pair differ (the heterozygous condition), then one determines the organism’s appearance and is called the dominant allele; the other has no noticeable effect on the organism’s appearance and is called the recessive allele. Thus, in the example above dominant purple flower allele will hide the phenotypic effects of the recessive white flower allele. This is known as the Law of Dominance.

The above data clearly follow all the law. As per given data first progeny are gray with long wings. So it clearly saw that gray colour and long wing is dominant allele. so when f1 crossed to male homozygous male

Phenotype

observed

Explanation

Grey,long

225

Low of dominance

Grey,short

283

Low of dominance, law of independent Assortment

Yellow,short

219

Low of dominance, law of independent Assortment

Yellow,long

277

Low of dominance,law of independent Assortment

Phenotype	observed	Explanation
Grey,long	225	Low of dominance
Grey,short	283	Low of dominance, law of independent Assortment
Yellow,short	219	Low of dominance, law of independent Assortment
Yellow,long	277	Low of dominance,law of independent Assortment