Biology Wed May 18, 2005 Homework: Warm Up: 1.Write out a set of crystal clear numbered instructions for HOW TO USE A MICROPIPET. 2.Each restriction enzyme recognizes and cuts at (one/many different) restriction site(s). 3.Small circular rings of DNA in a bacterial cell are called (sticky ends/ plasmids).

4.Plasmids (can/ cannot) move in and out of a bacterial cell. 5.Why in LAB B, was cabbage juice added to the gel box? 6.A sticky end is (double / single ) stranded DNA. 7.The DNA molecules has a (positive / negative ) charge. 8.What does buffer do? Why will we use it? 9.Write a palindrome. 10.Use the following terms to describe how ganetic engineers create a bacterium that produces a human protein product such as insulin. ligaserestriction enzyme restriction siteplasmid protein product madesticky ends recombinant plasmidDNA containing the human gene of interest.

Hold micropipet and epitubes at eye level

Micropipet Use Twist dial to desired volume 1 Twist dial to desired volume 2 Add disposable pipet tip 3 Press plunger to first stop 4 Insert pipet tip into solution to be transferred transferred 5 Slowly release plunger to retrieve liquid 6 Move pipet tip into desired tube 7 Press plunger past first stop to second stop to transfer liquid, keep the plunger down to transfer liquid, keep the plunger down as you remove it from the tube. as you remove it from the tube. 8. Eject tip

Micropipetting technique A

technique B Close the tips!

Technique C Billiard style

Micropipet tip should be ABOVE the well NOT IN IT!!!!

Micropipet tip punched right through the gel See dye under the wells

NICE!