Top Posters
Since Sunday
I
3
p
2
w
2
y
2
J
2
Q
2
r
2
o
2
e
2
j
2
d
2
T
2
SlideshowReport

The role of cell-signalling proteins in the morphology of birds' feet.

Description
This figure shows how changes in developmental gene expression can produce new traits. (a) Expression of the BMP4 gene in the developing limbs. BMP4 protein is stained blue here. (b) Expression of the gremlin gene in the developing limbs. Gremlin protein is stained brown here. Note that gremlin is expressed in the interdigit region only in the duck. Gremlin inhibits BMP4, which causes programmed cell death. (c) Because BMP4 is not inhibited in the interdigit regions in the chicken, the cells in this region die, and the foot is not webbed. By comparison, inhibition of BMP4 in the interdigit regions in the duck results in a webbed foot.
Related Images
Add Comment
Explore
Post your homework questions and get free online help from our incredible volunteers
  302 People Browsing
Show Emoticons
:):(;):P:D:|:O:?:nerd:8o:glasses::-):-(:-*O:-D>:-D:o):idea::important::help::error::warning::favorite:
Your Opinion
Do you believe in global warming?
Votes: 488