1/25/14 Turrentine students learn about vision
Photos by Sam Roberts / Times-News
Above, sixth-grade science students Makya Holmes, 11, right, and Jetzabel Gonzalez-Jimenez, 11, dissect a cow eyeball Friday in Sara Pasquinelli’s science class at Turrentine Middle School.
Turrentine students learn about vision
By Isaac Groves The Times-News 1/25/14
Reprinted with permission.
Sixth-graders, cow eyeballs and scissors — what could be better?
Sara Pasquinelli’s science class at Turrentine Middle School got some gloved-hands-on learning about the sense of sight Friday.
About 10 pairs of students get a red, foam tray carrying a roughly cylindrical mottled, off-white lump with a big gray spot at the end.
|Students take a closer look at how vision works by dissecting the cow eyeballs.|
Pasquinelli takes the eyes from a white three-gallon Carolina Biological Supply bucket. The Burlington science-education company gets them from slaughter operations, Pasquinelli said, and donated these to the school.
There are a lot of “Ooooos,” and at least one “I’m not touching it!”
Pasquinelli quiets her students with a time-out sign.
“Now, there’s a lot of brown and white around the eye,” she says. “What do you think that could be?”
“Muscle and fat,” says Deacon Mize. He is not the first to answer, but the first to get it right.
“Your muscles hold your eye in place,” says Ms. P, as most students call her.
The students in their aprons, gloves and safety glasses have 17 minutes to get that stuff off. One partner pulls it from the eyeball while the other takes little snips of the fatty and connective tissues, careful not to cut the nerve.
Pasquinelli holds a fat-free eyeball up to show them what they are aiming for. It should take the eyeball from about the size of a middle-schooler’s fist to size and shape of a large radish.
“Don’t be afraid to cut it,” Pasquinelli says. “It’s dead, and it won’t come back to haunt you.”
Jetzabel Gonzalez-Jimenez and Makya Holmes, both 11, get going. Holmes makes small cuts quickly. Her partner wants her to keep the scissors as a pile of mottled white lumps builds up on their tray.
A girl at a neighboring table pats her scraps into a patty and calls it a hamburger. A boy near the door got something on his arm above the glove and goes into a flailing dance, wiping his skin on the corner of his table and waving to Ms. P for rescue.
She ignores most of the unscientific behavior as long as the class stays on track.
“Do we have to cut up the eyeball?” Gonzalez-Jimenez asks her partner.
Holmes shakes her head, and keeps cutting. She is not correct.
Mize and his partner Miguel Hernandez are the first to get down to the eyeball. Theirs looks more like a head of garlic than a radish, but Pasquinelli gives it the nod. She gets her seventhgrade assistants to help push the job along.
Once the class is ready, Pasquinelli gets the seventh-grade experts to make the scalpel incisions so the sixth-graders can cut the gray spot at the end off with their scissors.
“Repeat after me,” she calls out, “cornea.”
“Cornea,” the class calls back.
Some look through it — a cow’s eye view.
One of the seventh-graders opens a window to let the smell of formaldehyde out. No one complains about the cold.
A lot of ‘oooing’ later, there is a lump inside Holmes’ and Gonzalez-Jimenez’s eye sitting atop some clear jelly. It is a bit reminiscent of a really old cherry cordial. They pour out the jelly.
“Everybody say ‘vitreous humor,’” Pasquinelli calls out.
“Vitreous humor,” the class calls back.
Students separate the little round disk lens from something that looks like an old gasket with their thumbs.
Before the class can dissect the lenses, though, it’s time for electives, Pasquinelli says, so line up by the door and get some hand sanitizer.
“Nooooo!” the class calls back and really seems to mean it.
And what have we learned today?
“I’m never touching my eyeball again,” Holmes said.
“Eyeballs are squishy,” Gonzalez-Jimenez said.