Molecules of Life

DNA

October 6, 2011 in DNA

The genetic code came to life for the 5th grade students in Ms Ippolito’s class at École FACE School on Tuesday the 24th of November, 2009, thanks to MoL Team DNA, Tanya Godina (chemistry MSc student U Montréal) and Dr. David Sabatino (PDF chemistry U Montréal). The so called “Molecule of Life”, deoxyribonucleic acid (DNA) was first introduced to the students by David, who employed a series of animations (for URLs see below), to teach the students the basics of genetics, cells, chromosomes, genes, DNA, SNPs (single nucleotide polymorphisms) and mutations. From the discussion that emerged, it was clear that the students knew all kinds of interesting information about genetics, particularly mutations. The students learned that DNA codes for the various proteins that determine whether we are a human, goat, monkey or banana. Humans share 99.5% of their DNA with each other. The other 0.5% of our DNA codes for our different traits such as our height, sex, ear shape, eye color and hair texture.

After this introduction, Tanya provided each student with their own DNA extraction kit and each of the 30 students extracted DNA from either a piece of banana, orange, apple or zucchini. Guided by Tanya, the students crushed up their fruit or vegetable sample, added it to a mixture of bicarbonate of soda containing some salt and soap, and shook up the mixture, which was filtered. To the filtrate, some cold rubbing alcohol (isopropanol) was added to create a two phase solution. The students were captivated as they watched the DNA precipitate at the interface of the two layers.

Finally, to give the students a taste of what it is like to decode the genetic code, Tanya and David shared a game in which the three letter codes from DNA were translated into one-letter amino acid codes which spelled out traits (i.e. blue eyes, pointed nose …), which were used to bring a picture of a new being to life.

Pleased to have the mystery of the genetic code decoded for them in a fun and informative way, the students thanked team DNA for teaching them all about genes.

For a great animated introduction to the world of DNA see:

http://www.youtube.com/watch?v=eOvMNOMRRm8

For an animated introduction to SNPs see:

http://www.youtube.com/watch?v=5raJePXu0OQ&feature=related

For an animated introduction on where your genes come from see:

http://www.youtube.com/watch?v=lJzZ7p-47P8&feature=related

For plenty of videos and information on DNA, replication, mutations… see:

http://www.historyforkids.org/scienceforkids/biology/cells/dna.htm

and the videos therein.

For more on how to extract DNA from fruits see:

http://www.funsci.com/fun3_en/dna/dna.htm

See our ‘Resource for Teachers’ poster : http://moleculesoflife.ca/category/resource-for-teachers/

Tags: DNA, Genetic
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Prolactin

October 6, 2011 in Peptide

Monday, April 23rd, 2007, Halifax, NS, 2nd graders were intrigued by the mixing and movements of color dye in a plate of milk as the team of Ted Abraham (BSc, SMU) and Wes Johnston (BFA, NSCADU) introduced the peptide prolactin, which they explained causes milk production. The students showed their own knowledge about the different kinds of milk, from both plant (soy milk) and animal (i.e. cow, goat, buffalo, llama and human) sources. Engaging the students in a poster about prolactin and a chart about the components of various kinds of milk, Ted relayed how different kinds of milk have different amounts of fat, calcium, energy and vitamins. Cutting shapes from card board tubes and paper cups, Wes guided the students in how to synthesize a peptide chain from alpha-helix and random coil secondary structures. Combining the helices and coils together, the students constructed a giant peptide chain, which they measured to be 10 meters long (now that’s a big peptide!). Milking the prolactin moment, the students grasped why polactin levels are usually very low in men and why in women, prolactin levels increase to a maximum immediately after childbirth. In addition, they were reminded that oxytocin, another peptide (shaped like a lasso) causes milk release called lactation.

Finishing our third MLP presentation in 2007, (10th total!!), team prolactin was thanked for a crème de la crème MLP experience in 2nd grade in Halifax.

Team Prolactin, Ted Abraham (BSc, SMU) and Wes Johnston (BFA, NSCADU) fielding questions on milk.

Exploring the influence of soap on color dyes floating on different kinds of milk.

Tags: Prolactin
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Oxytocin

October 6, 2011 in Peptide

Friday, February 16th, 2007, Halifax, NS, 2nd graders shook hands and shared the love of learning about Oxytocin thanks to the team of Emilie Crewe (BFA NSCADU) and Amy Holland (BSc SMU) in our first MLP in the New Year, hurray!!

Expanding and contracting rubber bands, relating stories of the comfort of a hug and the times that their pets had babies, looking at pictures of kittens and puppies suckling as well as watching parts of the classic film “101 Dalmatians” , the students were immersed in thought about how oxytocin performs three key functions: 1) to cause feelings of love from touching, 2) to cause contractions for babies to be born and 3) to cause lactation of milk from the mother. Considering that oxytocin is shaped like a lasso, formed by a string of amino acid building blocks, the students made oxytocin inspired lasso-shaped bracelets. Different colored beads represented the different amino acids, as each student constructed their own oxytocin bracelet to illustrate the loop of six amino acids, formed by a disulfide bond (the same kind of bond found in hair and in insulin), off of which three other amino acids dangle. All raised their oxytocin bracelets with glee loving peptide chemistry on a MLP Friday after Valentine’s day.

Finishing our first MLP presentation in 2007, (8th total!!), team oxytocin was thanked for sharing MLP love in 2nd grade in Halifax.

Team Oxytocin, Emilie Crewe (BFA NSCADU) and Amy Holland (BSc SMU) sharing the love of teaching about oxytocin

Studying the contractions of rubber bands.