Genes in a Bottle on the cheap

Commercial supply stores have kits that they are happy to sell you for $100 + per class. There's an interesting one called, "genes in a bottle" where you extract your DNA and place it in a microcentrifuge tube tied to colourful thread which you can wear around your neck.

If you wanted to do this at home, there is "shot glass DNA extraction" those uses over-proof rum and other household materials. For the classroom, though, I found an excellent method at about.com: biology. Here’s the link:
http://biology.about.com/library/howto/htdnaextracthum.htm

The method is rated as simple and only takes 15 minutes. The materials are easy to find: small plastic cups (like a medicine cup for rinsing your mouth), small beakers, test tubes with stoppers, distilled water, salt, liquid dish detergent and rubbing alcohol (95% chilled alcohol could be used if that was more plentiful).
Other advantages to this method are that you don’t have to put in an order and wait for it.
If you want to take the extraction a step further so that students can proudly wear their DNA, it can be spooled into an Eppendorf tube which can be tied with colourful thread. These microcentrifuge tubes can be purchased for about $20 for a package of 500. That’s "Cents-ible Science"!

Virtual DNA electrophoresis & make your own!

I am teaching gr. 12 Biology now and I have all kinds of fancy electrophoresis equipment. But that is not really necessary. Many university websites have lots of support for science activities. The University of Utah has a virtual tutorial where you learn to make and pour your own gels. It's fabulous and really reccommended for teachers and students alike. Here's the link:

http://learn.genetics.utah.edu/content/labs/gel/

If you want to make your own electrophoresis equipment with 5 x 9V batteries and a dish soap container attached to batteries with alligator clips, you could save yourself upwards of $2000!

Here's the link!

http://www.nexusresearchgroup.com/fun_science/electrophoresis.htm

You Tube is the Biology Teacher's Best Friend!

Recently, my student teacher impressed me with some little videos that he incorporated into a Powerpoint presentation. I use PP also with little videos that we watch online - Virtual Cell Animation Collection being a real favourite of mine (watch the lac operon video - excellent!).This got me to thinking and surfing You Tube and I was amazed at the plethora of videos that are out there! BIO-RAD has a few videos, one of which is a spoof of "We are the World" but it's about PCR. It's so over the top and funny!Beyond that, there are so many that are really good with excellent graphics and interesting music. There is no way that I could reproduce any of it in 2 dimensions.

Tie-Dye shirts with Sharpie Markers - no mess!

This is directly copy and pasted from the Steve Spangler website but I find that I really need to save this - it's a gem! I do paper chromatography with my students and have made beautiful patterns with the Sunday School kids for cards but this really is a good spin on an already cool lab activity!

Sharpie Pen Science A tie dye technique without the mess, using Sharpie Markers!
It's a brand new tie dye technique without the mess... and the results are amazing! This activity combines chemistry and art to create a designer t-shirt that is sure to get lots of attention whenever you wear it.
Materials
Pre-washed white t-shirt
Sharpie® Permanent Markers (Red, Orange, Yellow, Green, Blue, Purple)
Plastic Cup
Rubber Band
Rubbing Alcohol (70% from the Drug Store)
Dropper Bottle or medicine dropper

Link to see the video for the method: http://www.stevespanglerscience.com/experiment/00000032

Steve Spangler's Demo a Week E-mail

http://www,stevespanglerscience.com
I do not usually tout people's products but I recently visited the Steve Spangler website (http://www.stevespanglerscience.com/) and signed up to receive a weekly e-mail that features a different demo a week! It also shows a product that you can purchase but what can you expect?



This week's demo was the 7 layer density column, a colourful demonstration where you carefully pour different layers of liquids that settle into discrete layers due to their different densities. It is a demo that I already do, but he does it better. There are videos to show you how he does it and a full write up.



You can link to Steve's blog and it's really good for getting ideas! There are a lot of demonstrations shown of him on different TV shows and I have noticed that he doesn't always explain the science fully. One demonstration that I am keenly interested is the self-carving pumpkin (or watermelon). You carve the pumpkin from the inside, cut it to scoop out the content and make a hatch at the back so that you can insert materials to do the demonstration. Whatever reaction he does is explosive enough that it blows the eyes, nose and mouth out of the pumpkin! It is very cool! Now that I have heard about it, it's only a matter of time that I find out how!

Density Demo taken up a notch

I was helping out with our summer church camp and it was a science theme. They have a demonstration at the end of each day. The demo today really took my old diet Coke/regular Coke demo up a couple of notches.

First, put in a regular Coke, then a diet Coke. Ask for predictions from the audience each time about what they expect will sink or float and why.

Try:
Pepsi and Diet Pepsi
A lemon and a lime (the lime sinks, the lemon floats)
An peeled orange and an unpeeled orange (the orange floats, the peeled orange sinks)
And for a big finale, two bowling balls - one 7 lb and the other 16 lb (borrowed from a bowling alley). The 7 lb bowling ball floats and the 16 lb one floats!

And it's all about density and how tightly packed together those particles are. High density items (like people packed together on a bus during rush hour) that are more dense than water will sink. Low density items (like people in a bus during a slow time) will float!

Acid Rain Demonstration

Burningof sulphur – acid rain demonstration (Science & Society connection)
Apparatus: gas bottle, BTB indicator, glass plate, deflagrating spoon & sulphur.
Directions:
1. Fill gas bottle with water and add a few drops of BTB (indicator turns yellow in an acid or remains blue in basic or neutral solutions).
Put ½ tsp (amount is not critical) into the spoon and heat over the Bunsen burner flame. Ask a student to turn off the light so that the violet flame can be viewed.
Lower the spoon into the gas bottle, taking care not to touch the sides (see photograph). Cover with the glass plate. The white gas (SO2 and SO3) will billow and fill the air space above the blue liquid. Douse the flame in a waiting container of water (Safety alert – toxic gas produced is, use a fume hood).
Discuss with the class about societal and environmental implications of factories burning sulphur and the products that will come out of the smokestacks, like sulphur dioxide and trioxide. During this time, these two gases will dissolve into the water to form sulphurous and sulphuric acid, changing the pH from neutral to acid.
Cover the top of the bottle completely with the glass plate and shake once. The blue coloured solution will dramatically change to yellow. This indicates that the solution is now an acid. Explain how this demonstration shows how we get acid rain and the effects of air pollution on our lakes.
Extension: In Southern Ontario, there is a buffering effect of limestone (CaO) that will react with water to form calcium hyroxide (CaO + H2O--> Ca(OH)2). Since metal hydroxides are bases, this counteracts the effect of the acid rain. Therefore, Southern Ontario is not as affected by acid rain as it could be.

Silver flakes make for a cool demo

This is an oldie but a goodie. This is a demonstration that I never get tired of.

Single Displacement Reactions
Demonstration: Reaction of copper with silver nitrate.
Apparatus: coil of copper wire, large test tube, silver nitrate solution (concentration is not crucial).
Directions:
1. Place copper wire into test tube of silver nitrate. Allow students to review the activity series and predict the products of the following reaction:
Cu + AgNO3 --> Ag + Cu(NO3)2
2. Observe the reaction (see photograph). Large, beautiful flakes of silver come out of solution and the clear, colourless silver nitrate is replaced by a blue solution of copper nitrate. This colour change is evidence that the copper has gone into the solution.

Sex and Evolution - The Mating Game

PBS has excellent resources to support an important topic that will move down to the grade 11 Biology level in the fall of 2009: Evolution.

Here is the address: http://www.pbs.org/wgbh/evolution/educators/teachstuds/svideos.html

There are a whole series of videos which can be purchased or you can show a variety of 10 min video clips from a range of topics including:

Why is Evolution Controversial Anyways? How does Evolution Really Work? and Did Humans Evolve?

I like the range of topics because it goes beyond outlining what Evolution is about to why it is important and controversial.


As well, there are some fun parts like the sex and evolution dating game. There is a host, a contestant and 3 bachelors behind the curtains. There are questions that you can ask the contestants such as: what would be the perfect gift? The bachelors are different species of animals so what they think of as the perfect mate will be very different.

Chem4kids Website - Wow!

Wow! I came across an excellent website for kids called http://www.chem4kids.com/. It should not be called chem4 kids since there is a biology, astronomy and earth science sections, too!

I don't what the target audience is, but it's a great overview of things for high school students. It has colour pictures to add interest. Done by Rader Studios, they have done justice to the topic, doing a great overview and making sure to have real life examples

Breadmaking - a Fun Way to Connect Real Life to Science

I love making bread. There's the activation step with the sugar, water and yeast where you can see the activation of the yeast (frothing). There's the kneading and the rising, the punching and the rising again. It's a bit like magic! I guess that's one of the things that I love about science. There are so many things that are like magic.

There are many connection points for breadmaking in the curriculum. The most obvious is grade 9 Science in the Reproduction unit (asexual reproduction in yeast). Another is during the grade 11 U Biology Cells unit, there is a part about aerobic and anaerobic respiration. One of the aspects that is mentioned is that some of the products are alcohol and carbon dioxide. During the making of bread, it is the carbon dioxide that makes it rise. You could equally make wine for the same reason and the side product would be alcohol. Other connections is the Grade 12 Biology, Metabolic Activities unit.

If you don't have much time, you can use the breakmaker and just show the class the activation of the yeast. Or, you could have the water, sugar, yeast in a water bottle with a balloon on the end and collect the carbon dioxide. It is even possible to do a gas test by pouring the carbon dioxide over a candle.

World Clock - Watching the World's Population in Realtime

I came across the following website today while reading our Science Teacher's magazine. The address is as follows: http://www.poodwaddle.com/clocks2.htm

When you get to the page, you can view the number of people being born, dying, having abortions, contracting AIDS/HIV, being diagnosed with heart disease or cancer. You can click different buttons to look at the data per year, month, week or NOW. That is the scariest button of all. This would definitely be useful for grade 12 U Biology - Population Dynamics unit.

The interesting thing about this website is that although it is just numbers presented to us, what is selected to be shown is very revealing. If you look at the number of abortions, why would they include that? In Canada, we have no abortion law, since abortion is considered a medical procedure and other medical procedures have no laws associated with them. But if you click on the abortion button, you get a picture of a cute baby appears with a large number, indicating the number of abortions obtained while viewing it. You can also get numbers associated with the amount of botched abortions but it is not included in the main stats included with the World Clock. This can connect with the grade 9 Science - reproduction unit, beginning of life issues.

Other connection points for this website is Grade 11 U Biology - Biodiversity unit (Bacteria and Viruses section). Deaths by HIV/AIDS are a staggering amount but what is surprising how close a second is death by diarrhea-related causes. I think that I can assume correctly that with clean drinking water and simple medicines, that that number would be zero.

The Joys of Sidewalk Chalk

I took my Chemistry 12 students out into the parking lot with a bucket of sidewalk chalk last semester. We had been talking about s, p, d and f orbitals and I love doing role play. I do a lot of role play in Biology. We chose a small element and went through the energy diagram for it, placing electrons (running students) in one at a time. It was interesting the questions that came up or occurred to me while we were doing this. You could see more clearly that some of the orbitals would overlap and were of a similar energy. One could also see that it is interesting to "look" at the atom at such a minute level and "zoom" in, so to speak.

I found that some students found it quite helpful and some found it confusing or really unhelpful. That was worth thinking about because it told me something about what kind of learners that they were.

A number of colleagues asked me about it because they saw me heading out into the parking lot with a bucket of chalk and my grade 12s. Also, I was able to ask for clarification from another fellow teacher as we moved through it.

It was definitely worthwhile to break out of the classroom and I will be searching for more small ways to do so.

Show and Tell Science

My kids are 3 and 5 1/2. Their favourite day of the week is Friday, because it is Show and Tell day. I think that as we get olde r, we forget how interesting it is to share with others something that you are bursting to tell them. It really hooks people. I tried this concept with my grade 11 U Biology class last fall, with good results. There were a lot of things going on, so it fizzled out before the whole class did it, but I am going to try again next semester because we had some fun with it.

One of my students brought in a green, engorged caterpillar that was crawling on a tomato plant in his backyard. It was fun asking some of the teachers in school to identify it. I also asked Photogirl, who is a naturalist. She has a nature guide and made quite a good guess (without seeing it). Finally, the student did some web research on the topic and found out it was going to become a certain type of moth. The class was really into it.

As I was getting into the show and tell thing, my 5 year old was getting to the science demonstration thing. We put an egg in vinegar and let the shell dissolve. It produced bubbles right away and would spin periodically. After about a day or so, the shell was completely gone and the membrane was so tough that you could hold the egg in your hand and bounce it. Needless to say, we kept bouncing it from higher and higher until....it broke! But it was good fun and I got up to waist high before it broke. It's a perfect demonstration for cell transport (grade 11 U Biology) and quite a common one but I had never done it before.

The part II to this is that we put the shell-less egg into corn syrup and the water moved outwards, of course. The yellow bcame quite hard and it had a generally deflated appearance.
It was cool to touch and grosses out some people. You could measure the diameter of the egg before and after and/or take the mass.

My five year old was impressed with all of this and took it for her show and tell on Fridays!

Environmental Connections

I am thinking of having a small environmental activity for all my classes every Friday. I find that otherwise, students lack the ability to reflect upon these issues. Some topics might include:
1) Water use
Students make a log of how many times their household toilets are flushed in a 24 period and the total amount of water needed
A discussion could follow about how water use could be minimized.

2) The impact of fast food and trash generated
Students would make a diary of all the meals eaten during the week and estimate the trash generated
A discussion could follow about choices. If you are going out for a coffee with a friend, many places will serve your coffee in a real cup if you ask. You could just never drink coffee out of a take out cup.
3) Social justice issues - coffee and chocolate (Good connection for 11 U Bio, plant unit)
Have students do some web research about free trade coffee, chocolate and sugarBiobabe