Tag Archives: science

Jenna’s “Author’s Tea Party”

Today Kirsten and I had the opportunity to visit Jenna and her classmates for an “Author’s Tea Party”. Jenna read to us a non-fiction book and then a book she wrote titled, “All About Wildlife”.

She did a fantastic job writing and illustrating her book. She discussed classes of animals, geology and the environment, dietary requirements, evolution, extinction and predation.

While reading her book she skipped the following sentence so as not to offend her classmates or their parents:

None of anything is made by Mother Nature or God. It’s all called Science.

After each pupil read their book the group was allowed one comment and one question. After one boy read about “little stars” Jenna asked, “How do you know the stars are small unless you’ve seen one up close?” Brilliant question, I thought.

Jenna listened as Miss Holland addressed the audience

Jenna listened as Miss Holland addressed the audience

Jenna read to us a non-fiction book

Jenna read to us a non-fiction book

Jenna read to our group her book, "All About Wildlife"

Jenna read to our group her book, All About Wildlife

Jenna likes the science section best

Jenna likes the science section best

Jenna and Thomas, a past crush

Jenna and Thomas, a past crush

Jenna and her second grade teacher, Miss Holland

Jenna and her second grade teacher, Miss Holland

Kirsten: Something I Learned

I always wondered why cutting up raw onions makes me cry. Why does it make me so sad?

How Stuff Works provides a good explanation:

onionWhen you slice through an onion, you break open a number of onion cells. Some of these cells have enzymes inside of them, and when they are sliced open, the enzymes escape. The enzymes then decompose some of the other substances that have escaped from sliced cells. Some of these substances, amino acid sulfoxides, form sulfenic acids, which then quickly rearrange themselves into a volatile gas.

The gas reaches your eyes and reacts with the water that keeps them moist. This changes the chemical’s form again, producing, among other things, a mild sulfuric acid, which irritates the eyes. The nerve endings in your eyes are very sensitive and so they pick up on this irritation (this is why our eyes sting when we slice onions). The brain reacts by telling your tear ducts to produce more water, to dilute the irritating acid so the eyes are protected.

It is these same sulfur compounds that form the nice aroma when onions are being cooked.

There are various methods for preventing eye irritation while slicing onions. Among them are to stand as far away from the onion as your arms will allow, and breathe through your mouth (which reduces the airflow through the nose and into the eyes). Cooking the onion before you slice it will minimize the release of gas because the change in temperature alters the compounds in the onion. You may also slice the onion under water; however, you will wash some of the aroma out. Another way to avoid irritation is by not cutting off the root of the onion, or by doing it last, as the root of the onion has a higher concentration of enzymes.

Some suggest that placing a slice of lemon under your top lip, holding a sugar cube between your teeth, or holding a piece of bread (a quarter slice) between your lips will absorb the gas before it reaches your eyes. This makes me think of those “hiccup cures.”

Then again, you could risk looking silly and wear goggles. My personal preference: omit the onions.