Day 2-Order of the day:

Last observation of your adults Place adults back in original tanks (make

sure you check # on tanks) Harvest your embryos or adopt from others

who have some Count embryos/record Observe embryos using microscopes-draw

in booklet Clean out any debris in petri dish Place petri dish in light/heat box

Dissecting microscope – Easier to use than the other microscopes. Image is not inverted, lower magnification

2 light sources – one from above and one from below

Different magnifications Focus knob May want black felt under petri dish

• Observe the breeding tank. Do the fish look different? Do you notice anything on the bottom of the tank besides waste? If so, describe in your manual.

• Take breeding tank and return fish to their homes.• Obtain petri dish and fill ½ way with egg water

(blue liquid in squirt bottle)• Remove insert and use pipette to gently suck up

and transfer eggs to petri dish.• OR pour water through white net (fine mesh). Eggs

will gather in net. Invert net, and touch to egg water. They will transfer to the egg water in the petri dish.

• Look at your eggs under the microscope

Remove any garbage – Fish waste (poop), broken eggs, unfertilized eggs, etc..

Count the number of fertilized eggs and record in your manual

Draw eggs and label with Chorion, Embryo, and Yolk (High and Low magnification)

-Drawing must show details of anatomy-label all visible body parts.

-If you have shared embryos, make sure to record which groups received them. You MUST have complete record of ALL fish in your particular “family”.

-If you have adopted your embryos, you are responsible for obtaining ALL results from the WHOLE “family” of zebrafish you adopted from.

-Drawings must show details including labeling of all visible body parts

-Compare your embryos to sheets with embryonic stages-determine age of embryos in hours

-When petri dish contains a range of ages, try and determine the youngest and oldest among your embryos and record. Give possible reasons for this range.

Chorion – Provides a protectiveshell for the embryo

Yolk – Provides nutrition for the developing embryo

Embryo – Continued cell division eventually leads to a fish. What is the process of cell division called?

Use these terms to label your diagrams