Abstract
This chapter describes methods for setting up and preparing the instruments and tools needed for embryo operations. The methods for isolation and recombination of blastomeres in sea urchin embryos are discussed. Removal of the fertilization envelope is usually necessary for blastomere isolation and transplantation. The surgical isolation and recombination of blastomeres by hand includes techniques that were originally used by Hörstadius on sea urchin embryos. These techniques are very powerful and some embryologists continue to use them with only minor modifications. A disadvantage to these techniques is that they require much patience and practice. New techniques include similar surgical experiments but use micromanipulators to control the dissection needles and bulk methods. When doing blastomere transplantations, doubling the amount of calcium in the seawater results in greater adhesion of donor and host cells. The methods for surgical operation on starfish, amphioxus, ascidians, and hemichordates are also described.
