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		UV Radiation(samples #3 & #4) Irradiate sample #3 (10 minutes after fertilization) and #4 (30 minutes after fertilization). Use the same preset button on the UV crosslinker. Observe embryos and note differences in all three irradiated samples and the control. Embryos should be observed on the evening of the first day when fertilization takes place. Then observe once each day for the next three days. Record any differences from the control (tube #1). Preparation of fixed embryos for immunocytochemistry(all samples)
				1. Transfer 50 ml of your embryo cultures to centrifuge tubes. Spin at mark 4 for 5 minutes. Check that you can see a pellet of embryos at the bottom. Quicklypour off the artificial sea water (ASW). Try to remove as much as possible , but don't worry about a little ASW left in the tube. 2. Gently swirl tube to resuspend the embryos. Add 40mL ice cold methanol and allow to fix on ice for no more than 20 min. By this time, the embryos should have settled to the bottom of the tube. 3. Decant off the methanol and resuspend the embryos about 25 ml ice cold ASW. ON ICE, let the embryos settle to the bottom of the tube by gravity. 4. Decant off the ASW and resuspend the embryos in fresh ice cold ASW. Store in the refrigerator until needed. Embryos will settle. 5. Decant ASW, swirl to resuspend in remaining ASW. Transfer to four 1.5 ml microfuge tubes.