A classical experiment studying the fate determination of stem cells in the developing embryo uses the transplantation of somites from one organism to another. In such an experiment, a scientist transplanted somites 20, 21, and 22 from the right side of the neural tube from five-day-old developing quail embryos into chick embryos. The transplantation was performed in two orientations so that the order of the somites was sometimes reversed.
20
21
Use the passage to answer the question.
Suppose that somite stem cells commit to their cell fates by three days post fertilization. Which result would be MOST likely in the chick embryos receiving somites transplanted in the reverse order?
(1 point)
The organs ansing from quail somites develop in a normal order because local signaling molecules appropriately pattem the developing organs.
The organs arising from quail somites develop in a normal order because transcriptional programs activated in the
nucleus cannot be reversed
20
20
21
21
22
1221
Π
L
R
1
22
1211
1
20
R
20
21
22
Π
L
R
Chick
A)
The organs arising from quail somites develop in the reverse order because local signaling molecules appropriately pattern the developing organs.
The organs arising from quall somites develop in the reverse
order because transcriptionai programs activated in the nucleus cannot be reversed.
L
Quail -
20
1211
1
122
22
L