Answer:
Explanation:
According to the given information,
b/b = brown, b+/_ = Wild type (WT);
XvXv or XvY = vermillion, Xv+_=WT;
sc/sc = scarlet, sc+/_ = WT
b/b; XvXv =white eyed female, b/b;XvY = white eyed male
b/b;sc/sc = white-eyed male or female
You should have at least one b+ and one v+ to be WT(e.g. XvXvb+b =
vermillion female, not WT)
1. vermilion females × brown males Cross is: XvXv b+/b+x Xv+Ybb
F1: XvY b+b – vermillion males; and XvXv+b+b – WT females
F2: both males and females have the same ratios: 1/8 white, 3/8 WT, 1/8 brown and
3/8 vermillion
Xvb+ Xvb Yb+ Yb
Xvb+ vermillion vermillion vermillion WT
Xvb vermillion white vermillion white
Xv+b+ WT WT WT WT
Xv+b WT Brown WT brown
Cross 2 – reciprocal of #1: brown females (v+v+bb) x vermilion males (vYb+b+) F1 =
wild type females (XvXv+b+b) and WT males (Xv+Yb+b)
F2: females ¾ v+_b+_ (WT): ¼ v+_bb (brown)
Males 3/8 v+Yb+_ (WT): 3/8 vYb+_ (vermilion): 1/8 v+Ybb (brown): 1/8 vYbb(white)
Cross 3: scarlet females x brown males
sc/sc;b+/b+ x sc+/sc+; b/b
sc/sc;b+ is scarlet, that you need at least one sc+ and one b+ to be
WT
F1: sc/sc+; b+/b – all are WT
F2: no x-linked alleles in this cross. 9 WT: 3 scarlet: 3 brown: 1 white
scb+ scb sc+b+ sc+b
scb+ scarlet scarlet WT WT
scb scarlet white WT brown
sc+b+ WT WT WT WT
sc+b WT brown WT brown
Cross #4: brown females (b/b; sc+/sc+) x scarlet males (b+/b+; sc/sc) F1 b+/b ; sc+/sc
(all WT) F2 is the same as cross #3.
