Saturday, November 17, 2012

Cell organelles

The cell nucleus is not a brain.
The mitochondrion is not a power plant.
The Golgi apparatus does not stamp proteins with labels for UPS trucks to use.
The chloroplast cannot turn light into sugar.

It may be a sign of cultural madness that we teach cells as parts, and not much else. We break things down into components, attach a "scientifical" name, ascribe an analogous function that means as much as the scientifical name, and call this science.

Memorizing the parts (and the cell is no more just the sum of its parts than you are) will help our children develop their memory, and there are good reasons for that. But if that is the point, a child's time would be better spent memorizing things they can use (like the times table) or poems they can love (maybe "Blackberry Eating" by Galway Kinnell).

If the rationale is that we need more "scientists" or technicians or whatever you want to call people willing to drive an hour to sit in a cubicle contributing to the international economy manipulating human symbols so a few other humans can collect symbols that grant them inordinate power, well, maybe learning to recite that a mitochondrion is like a power plant (even if you have no idea how a power plant works) serves a purpose.

But it does not serve a child.

Howard Zinn once said "Our problem is civil obedience."
I bet he was a pain in the ass to teach.


Susan Eckert said...

Amen! But, it's much harder to put it all together. The easy part is memorizing (if the desire is there, of course). The hard part is using the analogies to tell a story of what actually happens. Worth it, I believe, because it's beautiful. And I think they are capable of seeing the beauty.

Power plant schmower plant.

Jeffrey Michals-Brown said...

The "parts" reductionism bothers me a bit, though less on principle than on incompleteness: it's important to stress the functional relationships among organelles. One way is to divide the class into teams and assign each organelle role to a person on each team. After working out a process that satisfies the teacher, teams could (for example) compete to see which could produce a short polypeptide faster, given a dna sequence, something for mrna nucleotides, and trnas with attached amino acids, and involving as many organelles as possible.

Doyle, I keep wanting to know your alternative when you rant like this. i've seen some really cool ideas from you in the past, like the idea of ultra-local science. What would YOUR ideal cell unit look like???

Jeffrey Michals-Brown said...

Analogies are okay, too, provided it's clear they're just analogies. But I WILL scream the next time I hear the nucleus called the brain of the cell. I prefer telling kids it's a library--but one with a very pushy and bossy librarian. Of course that's imperfect as well, since there is no librarian--the books and shelves themselves do the bossing... Sorta the same problem as having no "selector" in natural selection. Ties us in semantic knots trying to talk about it.

doyle said...

Dear Susan,

The easy part is, truly, memorizing, something our students did willingly (and easily) just a few years ago. Not saying that the change is good or bad, but many, maybe most, of the students I have today will not do this, for whatever reason.

(Mrs. Lehman, my chemistry teacher back in 1974, would have agreed with the students--she always said why memorize something you can easily look up, and that was long before the web existed.)

I think students are capable of seeing the beauty, but not until they have genuine interest, and not until they can see the relationships of organisms at the macroscopic level.

If you don't know that a plant comes from a seed, hardly can expect you to know anything about the microscopic world.

doyle said...

Dear Jeffrey,

I rant because I am struggling with this--if I could go back to the 1890's curriculum designed by the Committee of Ten, a far better alternative to the Committee of Arne.

"As studies in language and in the natural sciences are best adapted to cultivate the habits of observation; as mathematics are the traditional training of the reasoning faculties; so history and its allied branches are better adapted than any other studies to promote the invaluable mental power which we call judgment."

Biology was placed first because in 1892, biology was about classification and observation.

My AP students get a deep, rich understanding of the cell; they get to explore the flow of energy, the movement of matter, the incredibly complex interaction of function and form--it is, truly, something beautiful as Susan says above, and they are capable, should they choose to do so, of seeing the beauty.

My CP students have had no high school chemistry, no high school physics, and very little high school math. That is not to say they are not capable of learning what my AP students can learn--it's the same pool of students, separated by two years of further training.

It's like asking a kid with no background in music to practice scales--they cannot grasp why they should, nor connect the activity to anything that they understand.

SO I muddle through, using the usual dog and pony show to push them to know enough to pretend to the state they "know" cell biology.

If I ever leave teaching, it will be because of this kind of futility.

anthony diLemme said...

Totally! My students are blown away when I tell them that they don't have to memorize the periodic table. They must understand how the periodic table works and is organized. Love your blog.
Anthony Dilemme
8th grade physical science teacher-California
Jersey raised.

Susan Eckert said...

If a student has to open the textbook every time you discuss the nucleus or a membrane or a molecule of DNA to understand what you are talking about, then how far can you really expect to go in class? This is different from memorizing the periodic table, which would be completely silly. When you use the periodic table, you do know (or should) what an element is, what a proton is, what an electron is, what an atom is, etc. Otherwise, the period table is completely meaningless. You need to have some info committed to memory to make sense out of what you are looking at.

If there is to be "synthesis" or evaluation or whatever it is we're looking for these days, there has to be some building blocks to get there, something to work with.

Re: analogies, as imperfect as they are, I still believe we should use them. This stuff is abstract, they can't see it, can't feel it, can't hear it, etc. How can we know something then if we have no direct experience with it? That's why a first step in "knowing" these things (and how do you really know a nucleus) is to relate it back to something we do know. But the problem then is that students often go to the next step and relate it back to the function of the organelle.

Susan Eckert said...

Typo above. In last sentence, I meant that students often don't go to the next step and relate the analogy back to the true function of the organelle. This makes this memory device completely useless I think.

And it's a periodic table obviously. Doh. Not a period table.

Jeffrey Michals-Brown said...

Memorization has earned a bad name chiefly, I think, because teachers got lazy and stopped there. It's certainly true that memorizing stuff is time-consuming and dull. --when would we ever get to the higher-level stuff? But, as I think about it, is there any definition of learning that doesn't include memory? Can we really go any farther up Bloom's or other taxonomy with nothing more than Google on a screen in front of us? I'm trying to remember where I read this--or even the details--but it was a look at higher-level thought, and found that the bigger difference between sophiticated thinking and simpler thinking wasn't raw brain wattage, but rather the amount of information available for immediate use--which sounds like momory to me. (I'm sure I butchered the account in summary, but that was my take-away. --so much for my memory!) I took a licensing exam in chemistry yesterday, which gave me a more visceral appreciation of this--how much faster I could move when I knew the atomic weights in question.

Kathryn J said...

In my classes, we have been germinating seeds, dissecting seeds, and next week we will start to grow plants. My students are still struggling with the concept that food comes from plants. We had a long argument in one class where one student refused to believe that photosynthesis happened anywhere other than trees.

My students have very little experience with or interest in the natural world. Slowly, I think I am turning some of them around.

doyle said...

Dear Kathryn,

In the end, that is the best we can hope for, and in a real way, the best thing that can happen.

It's why you and I and so many others teach.