<%@LANGUAGE="JAVASCRIPT" CODEPAGE="1252"%> 3 independent

Genetic 342 A&B

Kenneth G Wilson

Professory of Botany

Assuming independent assortment

In Drosophila the following wild type alleles are used for analysis v (vermilion eyes), cv (cross-veinless) and ct (cut or snipped wing edges). Flies doubly recessive and homozygous (v+v+,cvcv,ctct) are crossed with flies singly recessive and homozygous (vv, cv+cv+, ct+ct+). Female progeny that are vv+, cvcv+, ctct+ are then test crossed with the tripley recessive males (vv, cvcv, ctct)

P1=v+v+,cvcv,ctct x vv, cv+cv+, ct+ct+

F1 =Wild Type - V+V, cv+cv, ct+ct x vv, cvcv, ctct (gametes v, cv, ct)

F1 gamete types exp obs

v

cv+

ct+

181

580

v+

cv

ct

181

592

v

cv

ct+

181

45

v+

cv+

ct

181

40

v

cv

ct

181

89

v+

cv+

ct+

181

94

v

cv+

ct

181

3

v+

cv

ct+

181

5

       

1448

oliver

This is our friend Oliver the parrotlet,

Oliver is a true parrot,

the smallest in the world.