8& GENETICS IN RELATION TO AGRICULTURE: 
autosomes. A vestigial white female produces eggs all of which contain 
an X-chromosome bearing the factor w and an autosome bearing the fac- 
tor v. Half the sperms, on the other hand, contain an X-chromosome 
bearing the factor W and an autosome bearing the factor V, and half con- 
tain a Y-chromosome and an autosome bearing the factor V. Conse- 
quently when the sperm cells which contain X-chromosomes fertilize 
the eggs, F, females of the genetic constitution Vo(WX)(wX) will be 
“8 
0000) 
0006 
0006 
Long Red ? Long Red Jd Long Red ¢ 
vera at 
Long Red 2 Long Red o Vestigial Red & 
0 
Long White 
ou 
Bue 
Long White ? 
0N06 
Long White ¢ 
008 
Long White & 
800 
CaCl ele) eie0 
ee a 
Long White 2 \Wiie'9 | Long White d ee 
Fig. 42.—F; gametes and I, zygotes from the cross, vestigial white female x long red 
male: Factor symbols: » = vestigial, V = long, w= white, W = red. 
produced. Phenotypically they will be long red. When the sperm 
cells which contain Y-chromosomes fertilize the same kind of eggs the 
F, males which result will be of the genetic constitution Vo(wX)Y. 
Phenotypically they will be long white. The reduction divisions in the 
I’, female will result in the production of four kinds of eggs as 
shown diagrammatically in the figure. They will 
constitutions: 
be of the genetic 
V(WNX) v(WX) ViwX) v(wX),. 
Similarly four kinds of sperm cells will be produced by the F, male 
and they will be of the genetic constitutions: 
V(wX) v(wX) VY 
vy. 
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