Tuesday, June 3, 2008Hi there everyone! It's me again. Hiaxx… Today I still need to go to school. Actually, as I had told you all, that today I had Life Science Enrichment programme on DNA. Actually it's quite fun. It is not as boring as I had thought. We got to do 2 hands-on activities .Yeah! Okay, I’ll tell you what we had done in today’s activity.
Even though this Life Science Programme was started at 0900 hours, we must reach there at 0850 hours. After that, I went up to the hall together. We then sat down according to our class. Then, the teacher said that each class needs to sit in two rows. Then, the teacher started the lecture on DNA. But, before that, the chair person had to give out a pile of worksheet and mark the attendance. From the lecture I had learned a few things and I will tell you some information on the DNA. DNA stands for Deoxyribonucleic Acid. The basic structure of DNA is a sugar phosphate backbone and two strands form a helical structure (A double helix). The four nitrogenous strands bases in DNA are Adenine (A), Thymine (T), Cytosine (C) and Guanine (G). Adenine will always pairs with Thymine and Cytosine will always pairs with Guanine. They are held together by hydrogen bonding. DNA is found at the nucleus of the cell. 46 chromosomes are found in a normal human being. DNA provides instructions for making proteins. DNA determines the features and characteristic of living organisms. After the lecture, different classes went to different lab. We went to the Physic Lab 2, which is at Level 4.
Then, we started to do the first activity which is ‘Making an Edible DNA Model’. For this activity, we need to have 2 Licorice sticks, Coloured gummies – 9 green, 9 pink, 9 yellow, and 9 orange, 9 toothpicks and a plastic container. First, we choose a sequence and write the complementary sequence. The first sequence is T A C G T A T G A and the second sequence is T G G T T T A G A. I chose the second sequence. Then, we assemble one side of our DNA molecule. A piece of licorice will form the backbone and gummies will be the chemical bases. According from Adenine (A) = Yellow gummies, Thymine (T) = Pink gummies, Cytosine (C) = Green gummies and Guanine (G) = Orange gummies. We then place a gummy on the end of the toothpick goes all the way through. Anchor the toothpick into the licorice backbone. Then, we match the chemical base pairs. Place the colored gummy for the matching chemical base on the other end of each toothpick. We complete our DNA model by attaching the other backbone so our model looks like a ladder. We then twist our DNA model carefully so that it looks like a double helix. Actually, Mr. See did come and see us. He told us not to eat the gummies as it is poisonous. -_-||| Actually, the teacher had already told us not to eat as it is put at lab, don't know for how long. :)
We then do the second activity which is the extraction of DNA from strawberries. Actually, we need to do this in a pair. But, I had no one to pair up so I do the activity. Then, I found out that it is not a really bad thing after all. Those people who are doing this activity in a pair had to share the DNA while I got to bring home all the strawberry’s DNA. Yeah! First, we need a strawberry, a Ziploc bag, 15ml of buffer solution, ethanol, filter, beaker, boiling tube, glass rod, and a dropper. We must be careful with Ethanol as it is very flammable and we must keep away from flames and sparks. First, we put the strawberry in a Ziploc bag. Seal the bag while pushing the air out of the bag and use our fingers and hand to crush the fruit for 1-2 minutes. Some of them were not crushing the fruit but hitting the fruit lor. Then, add 15ml of buffer solution to the bag and reseal the bag. Mix the mixture with our fingers for another 1-2 minutes. Then, pour the mixture from the bag through the filter over a beaker. Use a glass rod to gently move the mixture around to allow liquids to pass through the filter into the beaker. Pour the mixture from the beaker to a test tube and collect 2-3ml of the solution. Pour the alcohol until we see a layer of alcohol above the solution. Allow the test tube to stand for 2-3 minutes. We will observe white jelly-like substance floating in the alcohol. The white jelly-like substance is the DNA of the strawberry. Using a dropper, we fill our micro-tube with alcohol. We then collect the DNA using the micro-tube of alcohol and put a string through the micro-tube cap and we could bring it home! Yeah! That’s all for what we had did. Okay, that’s all. Bye! I will post again so please wait for my next post!!!!
♥ClariceChua♥sweet mem0ries♥ 6/03/2008 06:12:00 PM
ME
平安、健康、心想事成、美夢成真♥ ♥Currently studying atNanyang JC
♥The CCA is AVA(◕‿◕)
♥Hobby Reading
Msn | Facebook | Friendster [x]
TAGBOARD
Linkies
♥Clarice颜忆♥lovedd♥-Jiro 汪东城♥Aaron 炎亚纶♥Calvin 辰亦儒♥Wu Chun 吴尊♥HIM 华研♥♥Loves♥蔡♥♥♥努力学习争取更好的成绩♥♥健康快乐，★★ ♥♥天天开心没烦恼。★★♥♥29th October ★★
Welcome
Welcome to clarice-flora.bs.com
Strictly no spamming & copying !
Hate me ? Click Here ♥.
PAST-TenseMarch 2007
April 2007
May 2007
June 2007
July 2007
August 2007
September 2007
October 2007
November 2007
December 2007
January 2008
February 2008
March 2008
April 2008
May 2008
June 2008
July 2008
August 2008
September 2008
October 2008
November 2008
December 2008
January 2009
February 2009
March 2009
April 2009
May 2009
June 2009
July 2009
August 2009
September 2009
October 2009
November 2009
December 2009
January 2010
February 2010
March 2010
April 2010
May 2010
June 2010
July 2010
August 2010
September 2010
October 2010
November 2010
December 2010
January 2011
February 2011
March 2011
April 2011
May 2011
June 2011
July 2011
August 2011
September 2011
October 2011
November 2011
December 2011
January 2012
February 2012
March 2012
April 2012
May 2012
June 2012
August 2012
November 2012