Baby Dragons!

By Marilee

During our second session at Finkl, we explored the role of genetics in engendering the unique combinations of attributes that comprise us. When asked if anyone knew what a gene was, many of the girls shook their heads. Some said they had heard of it but didn’t understand what it meant.

We began our journey into the world of genetics by analyzing the process that takes us from the single cell from which we are created to the trillion cells that compose each of us. Your cells, the girls learned, are constantly dividing through a process called mitosis, a process that involves the replication of DNA and eventual creation of two cells from one. We illustrated this by lining up. I gave each student a strip of paper with a color on it. The first line represented one set of chromosomes, and the second, paired evenly with the first, symbolized the copies. During prophase, the initial stage, the girls learned that DNA is copied, that the chromosomes in the cell — the organized structures containing DNA — normally hard to distinguish in the cell’s resting state, condense and become visible. The girls then lined up next to their “copy,” enacting the condensing of chromosomes that occurs during metaphase, the next step of mitosis. The lines moved a foot apart, mimicking the movement of the chromosomes to opposite sides of the cell during anaphase. Finally, during telophase and cytokinesis, the chromosomes arrive at opposite ends of the cell, and the cell divides, forming two identical daughter cells, which the girls depicted by moving to opposite sides of the classroom.

But if mitosis creates two identical daughter cells, how do we end up the unique gene combinations that make up each of us? The girls shook their heads. They didn’t know. It seemed odd.

To make the zygote, the single cell from which we come, the girls learned, the body uses a process called meiosis to create haploid cells — that is, cells with only one set of chromosomes. Our typical cells are diploid and have two sets of chromosomes. The mom donates one haploid cell, and the dad donates another to create a zygote, which itself is subsequently diploid. Meiosis enables the creation of haploid cells and therefore necessitates a process called crossing over, or gene recombination, a process the students illustrated by again lining up next to their “copies,” ripping their strips of paper and exchanging a piece with their neighbor, thereby creating sets of chromosomes that looked nothing like their originals. They then went through the process of dividing into four different groups, copying meiosis’ production of four daughter cells.

Melina and Ninel exchanged looks. The lesson was informative, sure, but maybe a little boring?

So why, I asked them, is the idea of meiosis so important?

“Because that’s how we’re different from each other?” Kathy offered.

Exactly! It has to do with the idea that different gene combinations can result and create a zygote with features derived from both parents.

To illustrate how influential different traits can be, and how scientists can determine the likelihood of a child inheriting certain traits from his or her parents, we examined the role of dominant and recessive alleles through Punnett squares and dragons. Yes, that’s right — dragons.

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We created a scenario in which we had fire-breathing dragons and non-fire-breathing dragons, winged dragons and wingless dragons. Fire breathing and wings were dominant traits, which meant even if the dragon had genes for either fire breathing or wings, said dragon would express those genes, regardless of other genes. To be wingless or not fire breathing, however, the dragon would need both genes to have those recessive traits. This, the girls learned, is the difference between a person’s genotype — the genes s(he) has — and the phenotype — the expression of those genes.

The girls loved drawing Punnett squares with partners to see what baby dragons would result from their crosses, seeing the diversity stemming from gene recombination.

When we finally journaled, Denise shared that she “used to think genes just meant the jeans you wear,” but now she knows that “genes create who you are.” Many of the students reiterated that sentiment, with Kathy adding that now she knows “that you get genes from your parents and they decide what you look like and that crossing over means you could look a lot like one parent and not as much like the other.” Lesly interjected, “Like when one parent has blue eyes and one has brown eyes, you might have brown eyes because brown is dominant.”

The students like learning the underlying — if basic — principles behind their genetic makeup and can’t wait for the next lesson!

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Forgery at Finkl

By Marilee

Our first class at Finkl Academy in Pilsen comprised a great group of girls eager to begin their Sisters4Science journey.

“Can we talk about the solar eclipse?” one asked before we even entered our classroom.

“Or paleontology?” another chimed in.

I quickly allayed their fears; they would fill out a questionnaire about their interests and hopefully, we’d get real scientists to visit and discuss their fields! The girls’ eyes lit up.

photoWe started the class with a quick ice breaker, creating a human knot from which the girls had to disentangle themselves using both verbal and nonverbal communication. The students loved it!

“It takes a lot of teamwork to do this,” Melina said.

“Yeah,” Margarita piped in, “you really have to learn to say what you want without speaking. It’s hard but lots of fun!”
We then got in a science circle to discuss positive and negative experiences with science. Most felt science was interesting and had predominantly positive experiences with the subject thus far.

“I like everything about it, except bugs,” Jade shared.

Everyone nodded emphatically — they enjoyed everything about science, save for the study of insects.

We then created our code of conduct. Each girl had a limitless number of sticky notes on which she could jot down her ideas for how we’d behave in the classroom. They posted their sticky notes on a white sheet, and we discussed and voted on all of our ideas.

Everyone agreed they wanted a respectful classroom, a safe space where they felt they could be heard without judgment or criticism, where they could share their voices without fear of being tread on by someone else. We agreed to be kind to each other, to give everyone a chance to participate, and to be inclusive and welcoming. The students especially enjoyed the idea of using the call and response “one diva, one mic” to call order to the room and liked thinking that the talking piece — a camel — signifies that only the person holding it may talk, symbolizing everyone’s moment as a diva in the room.

After carefully crafting our code, we journaled, using the prompt, “I use to think…, but now I know…”

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Everyone had wonderfully creative things to say, stories that centered on once thinking science a boring subject but then coming to the realization that it can come alive, that they could come alive while exploring what it had to offer.

“I used to think science was just about boring things like the periodic table,” Joselin said, “but now I know that it’s very interesting and gives you an opportunity to study cool things like nature and the stars.”

We ended the class by diving into a lesson exploring penmanship and forgery. Each girl attempted to copy a check — to forge the written items and the signature — discovering how hard it is to capture every nuance and defect inherent in individual writing.

“It was hard,” Nimel said. “And scary to think people can do that.”

They loved the lesson and asked for more hands-on activities next class. We can’t wait to begin again next Monday!