Question

5. (4) What will appen to dorsal/ventral patterning in Xenopus under the conditions listed below (a-h)? From the choices (1-3), select the single most plausible outcome for each experiment. 1. No dorsal structures form. 2. Normal embryo development. 3. Extra dorsal structures form. a) Fertlization followed by a brief UV treatment and physical rotation of the b) Fertlization followed by a brief UV treatment, then transplant of a ventral c) Transplant of a dorsal vegetal blastomere from a normal embryo to the vegetal blastomere from a 32-celled embryo onto the dorsal vegetal side of a UV treated 32-celled embryo. ventral hemisphere of another normal embryo at an equivalent stage. d) Fertilization followed by a brief UV treatment, then transplant of a dorsal vegetal blastomere from a 32-celled embryo onto the dorsal vegetal side of a UV treated 32-celled embryo. e) GSK3 overexpression throughout a normal embryo. t) Inhibition of Dsh from being made in the oocyte using RNA g) Vg1 expressed uniformly throughout the embryo. h) Treatment with lithium immediately after fertilization. (Note: lithium has the ability to inhibit GSK-3) Prtscrhert 5 6 8 0 W E s DFH B N M

Answer 1