Fig. 1.

Tools used for micromanipulation of 6.5–8.5-d mouse embryos. A The glass needle, B the holding pipet, C the injection pipet used for delivering dye or DNA solution, D the pipet used for grafting cell clumps, and E the two bends produced in the pipet (shown in B–D) to enable the tip of the pipet to reach over the wall and access the medium drops sitting on the bottom of the culture dish during micromanipulation (for setting up, see Fig. 5B).