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The Human Body: Cells and DNA

August 29, 2011

We love studying science with friends. Frankly, everything is more fun with friends, but since our friends can’t live in our basement, we have to import them whenever possible. Currently, we’ve convinced some to come over for a diabolical study of the human body using Dr. Frankenstein’s Human Body Book as our guide. This is a fun book with the right amount of science for our upper elementary students. You can see an in-depth review on The Pioneer Woman’s homeschooling blog here.

The Bean assembling the red blood cell model.

I managed to plan in advance for this session, and the kids rotated around to different stations in the basement: a book station, a microscope station (with some microscopes, a book, and a diagram to label), an animal cell station (with a model to build and a diagram to label), a red blood cell station (where they built a model and made their own sketches), and a white blood cell station (also with a model and sketch pad).

Inspecting some fuzzy strawberries at the microscope station.

One of Dr. Frankenstein's lab assistants being diabolical at the white blood cell station

Reading lab procedures: a must for Dr. Frankenstein's lab assistants!

After completing all the stations, they were ready for a little recess. The Bean changed into her Cleopatra costume and the boys grabbed various styrofoam weapons, and there was some kind of game that involved passwords and danger. 🙂 Then, still partly in character, our adventurous students were ready for the DNA activity. We are using a Science Wiz DNA kit. After some light reading and review about cells and DNA, they gathered their materials to extract DNA from some strawberries. This is a very cool experiment involving some basic household supplies, a few things from the kit, some strawberries, and some ice-cold denatured alcohol.

I love this experiment! It's simple enough that the kids can do it themselves, but it does require attention to detail.

The kids did a great job following the lab procedures and they extracted some gooey strawberry DNA. They are contemplating using it to build a strawberry-headed monster. 🙂

See that gooey stuff at the top of the vial? That's strawberry DNA!

 

Here’s the set of review questions I put to the students: 

Dear lab assistant trainees,
Way to go! We learned a lot today. Before we move on in our diabolical lab experience, let’s review what we covered today. You can take some time at the beginning of our next training session to look up any answers you don’t remember from today.
Like everything else in the universe, the human body is made of ___ ___ ___ ___ ___ and ___ ___ ___ ___ ___ ___ ___ ___ ___. Up to 60 % (or 6/10) of a human’s body weight can be attributed to ___ ___ ___ ___ ___ molecules. In living things, the molecules are so awesome that they build ___ ___ ___ ___ ___, the living units from which the body is made.
Cells and DNA:
The outside of a cell is called the _________________________________________________.
The jellylike fluid that fills each cell is called ___________________________________________.
The tiny structures inside the cell are called _________________________________________________.
The ____________________________________ release energy to power the cell’s chemical reactions.
The _____________________________________________________________________________________________ makes and transports proteins.
The _______________________________________________________________________ packages and distributes newly made proteins.
The ______________________________________________ is the cell’s control center. It contains _________________________ (a number) molecules of DNA.The DNA molecules contain about 25,000 instructions needed to make a body. These instructions are called _________________________. They control the production of ______________________.
Proteins are made of smaller molecules called __________________________________________________.
Different proteins do different things. They are in charge of organizing all the body’s other molecules.
DNA molecules carry a code to define what makes up an organism. This code has four letters: ___, ___, ___, and ___.
There are many different kinds of cells. Red blood cells contain _________________________________________, which is red when it is bonded to oxygen and blue when the oxygen is depleted. There are different types of white blood cells. Our white blood cell model is of a phagocyte. It helps mop up and destroy foreign bodies that cause disease, like ________________________ and viruses. We watched a video of a white blood cell chasing and catching ___________________________ (same answer as previous blank).
Madly and scientifically yours,
Mrs. Frankenstein

 

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Pot roast

August 2, 2011

I’m recycling an old Facebook note because it has come to my attention that pot roast is not in everyone’s repertoire, WHICH IT SHOULD BE, and I am unanimous in that.

There are only a few essentials for pot roast:

Wine and broth and veggies.

1) A Dutch oven (which, if it’s enameled and made by Le Creuset, may be called a French oven and is also eligible for use);
2) A cheap piece of meat;
3) Onions;
4) A 350-degree oven;
5) Liquid and salt.

Other stuff is optional. I’m debating about whether celery is essential or optional. Hmmmm.

Here’s the general idea:

For beef pot roast, use a chuck roast. I’ll deal with pork in a minute. Put your Dutch Oven on the stove and heat it up. A little past medium. Let’s say number 6 or 7. Hit it with a little oil. Let’s say a tablespoon maybe. Dry your roast with some paper towels and sprinkle some kosher salt on it. If you don’t have kosher salt, pick some up, because I don’t know how anyone cooks without it and I would totally ruin all my food if I tried to use table salt in the kitchen. I rely on the medium/coarse flakes. Anyway, put a little salt on it and grind some pepper on it.

Getting seared.

Oh, preheat your oven to 350. That’s important.

When the pot is hot, sear all sides of the roast. Each time you put down a new side, listen to the sound it makes … the sound will change when it’s seared and you can turn it to another side. It’s a learning process. If you try to pick it up and turn it too soon, it’ll stick. If it doesn’t want to release from the pan, give it a little more time. Gosh, I hope I’m not steering anyone down the wrong path here … don’t burn it, but do sear it.

OK, once you’ve got all sides seared, turn off the heat and lay the roast flat in the bottom of the pot. It’s time to add liquid. You can add water and salt. You can add chicken broth. You can add beef broth. You can add beef consomme. You can add canned tomatoes in their juice. You’ve got options. Put some liquid in there, BUT NOT TOO MUCH. Read the rest of this and you’ll know how much to put.

Searing the last side of the roast while the onions get happy in the pot.

You also need to put a bunch of onions in the pot. You can put a bunch of other veggies in there too, and I highly recommend that you do, but for heaven’s sake, don’t leave out the onions, unless you want to use a bunch of garlic instead, which I bet would work out OK, but if you don’t put onions and/or garlic in it it won’t taste good. I put at least one small onion in, preferably two plus some whole garlic cloves. I cut the onions in various ways … it really doesn’t matter.

After onions, the next most important thing to put in is celery. It’s best if you put in some celery leaves; they add the very best flavor ever.

This is a pot full of veggies. I was having a vegetable population crisis. I should have used my big pot!

You can also put in some other veggies. Now, Cooks Illustrated will tell you to do this later, because they don’t like their carrots and potatoes all mushy. Me, I’m OK with mushy, plus I might forget to put them in if I wait, so I put them in at this point. Classic pot roast veggies include potatoes, carrots, parsnips, and mushrooms. Cut them to about bite size if you want. Or put them in whole and cut them later; either way works great.

Roast on veggies in liquid in the pot, ready to be covered and put in the oven.


So I usually put in a little liquid, add my veggies and get them down around the roast, then add the rest of my liquid. YOU WANT THE LIQUID TO COME ABOUT HALFWAY UP THE ROAST. You do not want to boil the roast; you want to braise it. If you need to make an enormous amount of food, you can put the veggies down first, then put the roast on top of them so that it’s halfway out of the liquid.


Now, put the lid on your Dutch Oven and put it in the oven. Go do something else for an hour. Check on the roast. How’s the level of liquid? If it’s getting low, add more. Go do something for another hour. Check on the roast and TURN IT OVER. So, to repeat, turn it over after two hours. Add more liquid if it needs it. Go away again and come back after another hour. Check the roast. If it’s so tender you can mash it with a fork, it’s done and you can either take it out or take off the lid and cook it for another 15 minute or so to dry out the top. If it’s not fork tender yet, cook it until it is, which would only be another half hour or so.

All of which is a long way of saying: season and sear the beef, add seasoned liquid and veggies, cover, and bake at 350 for three to three and a half hours, turning the roast once at around the 2 hour mark.

You should end up with a bunch of food, some of which you can freeze for later.

OK, now pork. I use a Boston Butt/pork shoulder roast. Same deal with drying, seasoning, and searing. I usually add two thinly sliced onions, salt and pepper, and chicken broth. Sometimes I add tomatoes. Sometimes I add a little balsamic vinegar. Sometimes I add apple juice. On those unusual occasions when I have a bottle of Coke lying around, I’ll add that. (Pork likes sugar and acid.) But basically, if you sear and braise it the same way as a beef roast, you’re golden. It’s going to be fall-apart-in-your-mouth tender, and if you put enough onions in, it will taste great.

Line design and shading art project

August 1, 2011

I borrowed some of the other kids in the neighborhood to come hang out with us and have some fun learning experiences for the past week or so. We have all had a blast! One of the things we did was this really cool and easy art project. The kids rocked this:

Our friend C working on his project. He used a black pencil for his line design and chose not to add color.

The Bean working on her project. She used a roller ball pen for her line design.

Our friend G working on her project, using Sharpie for her line design.

Our friend K working on her project. She incorporated a pebble design. She is wearing a kimono because we are also studying Japan.

K's work in progress showing her vivid shading and finished line design.

The Bean's finished project. Please ignore the fact that it is upside down.

How to make tea

August 1, 2011

This post brings yet more fuzzy iPod Touch pictures made nearly abstract by Instagram. I hope they are sufficient to tell the simple tale of how to make tea from loose tea leaves. I get the impression that brewing tea without a tea bag is perceived as a rather high-falutin’ mystery.

Life contains many mysteries. There are, I’m sure, many mysteries associated with tea. However, making tea for consumption by ordinary mortals in the course of an ordinary day is a simple matter.

What you need are hot water and loose tea leaves. First, you combine them. Then, you separate them. Then you drink the tea.

I will elaborate, because I’m not really THAT obnoxious, but that is the essence of the process and the thing to bear in mind if you have tea and water but not much else. There is a lot of room for flexibility.

You may be wondering where one even gets loose leaf tea. We order ours from internet specialty stores such as The Tao of Tea, Tea Trekker, and Golden Moon Tea. One of our stand-by teas, which makes great iced tea or hot tea and is very forgiving of wacky brewing methods (and therefore goes camping and traveling with us), is this Sinharaja. We love this Emperor’s Gold at breakfast.

You might want to try a sampler from Tao of Tea or the 31 best-selling teas from Golden Moon. A sampler set kicked off our obsession, and it’s tons of fun to try lots of different teas.

You could buy some loose leaf tea at a grocery store, but those teas are probably not similar in quality to what you’d get from certified tea nerds. But it might still be lots of fun to try, so don’t say I told you not to do that. 😉 World Market has several looseleaf teas for $8.99 a bag, and I have recently discovered that if you join their Explorer’s program they will send you a $10 gift certificate for your birthday, so if your birthday is coming up, that’s one way to score some free tea.

Close to 185 degrees.

Once you have some loose leaf tea to play with, I recommend actually reading the brewing instructions on the package. A lot of our teas suggest brewing with 185 degree water. We are geeks and actually use a thermometer. That doesn’t mean you have to. I’ve also discovered that if I bring my water to a full boil, turn it off and open the kettle, about four minutes later it will be about 185 degrees. So I usually set the timer so I remember to come back at the right time. I get annoyed when I let the water cool down too long. 😉

Most of our teas are the sort that use one teaspoon per cup. This is not rocket science; the tea will not explode if you use a little more or a little less. I’ve found that a pretty big pinch between my thumb and finger approximates a teaspoon; this information is especially valuable when camping. (I could leave the tea at home, not just the measuring spoons, but I am much more pleasant after a cup or two, so it’s better for me to bring the tea.)

Starting the brew time: 4 minutes.

So, now you have hot water and loose tea. It’s time to combine them. You can do this in pretty much any heat-and-waterproof container. Here, I’m using a canning jar, because I’m classy like that. I often use a 2-cup Pyrex liquid measuring cup. At this point, you have to have a game plan for separating the leaves. For this mason-jar brew, I’m using a Bodum basket-style strainer that came from a set like this. When the tea is done, I just lift out the basket containing the leaves. A teaball is similar in concept, and a large teaball works well when your vessel has a wider lid than a tea cup or mason jar.

This is now one pint of hot tea.

The other way to go is with a strainer. If you don’t have any of this equipment, I bet you have some kind of strainer, maybe a flour sifter, maybe some cheesecloth … something. Or maybe you will just pour the tea into a teacup and use a spoon or something to keep the leaves in your brewing vessel. You possess sufficient ingenuity to separate tea leaves from tea, I just know it. 🙂

If you are going to sweeten your tea, which is really a whole other subject, now is the time to do it. I don’t, notwithstanding my 100% Southern pedigree. My husband adds a little honey to his. A lot of people like to sweeten tea with a simple syrup. Do as you will.

The real issue is whether you’re going to ice your tea. If you do ice it, you’ll want to brew it double strength. It’s about 100 degrees today, so iced tea is a matter of self-preservation. I think you know how to ice it. 😉 This will mean going from a pint-size jar to a quart-size jar. 🙂

Finished product: one quart of iced tea. Ahhhh!

Sunflowers, continued

July 19, 2011

Sunflower No. 1, all bloomed

The whole patch, July 13, right before ...

Sunflower No. 1 flopped over!

The whole patch, all bloomy

July 19: Some of the interior blossoms are falling out and you can see the seeds behind them.

Buddy making some observations

Sunflower No. 2 is flopping, too!

July 19: This is our miracle sunflower. Daddy plucked it before he realized it wasn't a weed, then replanted it. Then Mommy plucked it because you're supposed to thin out the poor performers, but Buddy protested, so we replanted it AGAIN in a pot. It's small and late, but it looks like it's going to bloom anyway!

Sunflowers

July 18, 2011

Buddy’s 4K teachers sent him home on the last day of school with a package of sunflower seeds. The stars and planets were favorably aligned, and we happened to have some dirt available in full sun where we would not be mowing for awhile. Next year, we’ll be mowing there. This, then, is the year of the sunflowers.

I’ve been taking some progress pictures:

Not quite a flower.

The first blossom.

Now the mini-flowers in the center are blooming.

See how the center is filling in?


More blossoms almost ready

More blossoms starting to show. Note the bee on the biggest flower and how its center has filled in.

Beach trip box

July 13, 2011

Really, why would you go anywhere without your microscope and a bunch of flash cards?