Crystals, Acids, and Digestion

Hi everyone!

It's been a busy few weeks. The borax crystal necklaces are finally complete and home with everyone. Two weeks ago, we explored the pH of common substances with a color changing indicator and learned that foods tend to be sour (acidic) and non-foods bitter (basic).

To show the effects of acids and bases on inorganic and organic material, we examined eggs. The kids first investigated century eggs, which are raw duck eggs that have been cured in lye for several months, then dunked fresh chicken eggs in vinegar to see what happened.

From there we moved on to our own digestive system and how food is processed. The human digestive system contains both acidic (the stomach) and basic (small intestine) sections, as well as a lot of other features shown on the worksheet. Make sure that's finished for next week, when we'll be finishing up digestion and focusing on enzymes.

Also, while not related to our current topic, here's a video of a juvenile (note the mouth color is pink) raven seeking human aid after getting several porcupine spines stuck in its face (ravens enjoy pulling the tails of other animals, which is probably how this happened).



Ravens are very intelligent and can teach their young to distinguish between friend and foe. This raven's parents must have been helped by a human or seen a human helping another raven and taught it to go to humans for help.

Crystals!

This week we did crystals! Specifically, we talked about crystal structures, then made a supersaturated sugar solution and dipped a string in it to grow rock candy.

Next week, we'll examine salt crystals and different crystallizations of sugar.

In the meantime, here's an example of a particularly weird result of crystallization.




(We will not be doing this in class due to it involving 100% too much exploding glass.)

Science Olympiad Heredity

Hey, heredity groups!

(If you need a refresher, check out http://www.siskiyous.edu/class/bio1/genetics)

http://www.quia.com/quiz/806830.html
http://www.proprofs.com/quiz-school/story.php?title=block-4group-2
http://www.biology.arizona.edu/mendelian_genetics/mendelian_genetics.html
http://www.ksu.edu/biology/pob/genetics/intro.htm
http://www.ksu.edu/biology/pob/genetics/dragons.htm


If you feel like a challenge, try out http://biology.clc.uc.edu/courses/bio105/geneprob.htm and see how far you get.

If you run into difficulty, you can comment here or email me and I'll do my best to help.

Physics is why fun things happen

We've entered the new unit of PHYSICS. If something is happening, physics is involved. If something isn't happening, physics is still involved! Physics lies underneath just about everything in science like a sort of science skeleton, because it deals with matter and we're made of the stuff!

Today, the physical properties of snow mean we've canceled class. (Makeup will be this Saturday or Monday, details in the email I sent.) Luckily, the physical properties of the wires and servers that make up the internet mean I can post something on the blog to make up for it.

So pull your kid over and remind them there's no escape from learning!

Consider this video:



Like most things on the internet, it's a funny cat video. And the humor couldn't happen without physics. Try making a list of everything happening in this video. Which ones do you think were because of physics?

Here's another:



What happened here?

Finally:

While this is obviously proof skateboards are deadly, can you see what specifically went wrong?  We'll be doing an experiment with washers in next class that will take advantage of this aspect of physics! Also, notice how the boys are falling like pros, minimizing their injury. We'll be talking about (but not practicing!) this next class.