Category: Cobb Vicki

The Mystery of the Alternating Nostrils

11/14/2022

Vicki Cobb
The Master Chef of Kids' Hands-On Science

Are your two nostrils exactly the same size? Don’t struggle to find out by looking in a small mirror. Put your nose right above the mirror and breathe down on it. You will see two circles of moisture as the warm moist air from your nose condenses into water when it hits the cool mirror surface. One circle will be a LOT larger than the other.

    You might conclude that yes, one nostril is bigger than the other; that you will have to live with being lopsided. But wait! I mean wait an hour or so and do it again. Surprise! This time the small nostril is now the BIG one! The larger nostril is dominant and takes in more of the air. You can do scientific study of your nose and see just how long each nostril dominates. Perhaps if you check often enough, you’ll discover a time when the two circles will be about the same size. This will be the moment of the changing of the nostrils. Of course, you have to do this study when you don’t have a stuffy nose.

    What’s behind this? It seems that your nostrils are on an automatic timer from your brain so that they take turns being dominant. It’s very interesting. But I’m not sure if it is important.

    Not many people know about this. But your dentist might. A dentist is always looking at peoples’ nostrils. See if your dentist knows about this. He or she might even know why this happens. This just might be a medical mystery worth investigating. And you might be just the one to do it.

Vicki Cobb ‘s “Discover Your Senses” series of books are available through the iTunes store. She begins by asking: “Know how to stop smelling? Hold your nose.” Also, check your library for copies. I mean wait an hour or so and do it again.

Vicki is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Cobb, Vicki. "The Mystery of the Alternating Nostrils." Nonfiction Minute, iNK Think Tank, 21 Nov. 2017, www.nonfictionminute.org/the-mystery-of-the-alternating-nostrils.

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Some Painful Truth

10/24/2022

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Vicki Cobb
The Master Chef of Kids' Hands-on Science.

How well do you handle spicy food? Do you find food with a “kick” eye-watering and difficult to swallow? Or are you a real “fire eater;” nothing can be too hot?

A scientist, named Wilbur Scoville, figured out how to rank spicy food for hotness in 1912. The “heat” from peppers comes from a chemical called capsaicin (cap-say-sin). Pure capsaicin registers 16 million heat units on the Scoville scale. Zero is a sweet green, red or yellow pepper. A fresh, green Jalapeño (ha-la-pen-yo) is rated 2,500-8,000 units, a lot less hot than pure capsaicin.

The fact is that you don’t “taste” the heat. The sensation of heat comes from nerve endings in your tongue that respond to pain. Of course, these nerve endings are not just in your tongue. They are all over your body. So a good scientific question is: Can you “taste” hot sauce with, say, your wrist?

Check it out. Rub the inside of your wrist with a cut Jalapeño pepper or some hot sauce. Wait a few minutes. Feel the burn? Rinse off your wrist well with cool water.

Your tongue, of course, is much more sensitive than your wrist to many chemicals because it is always wet. Capsaicin, like a lot of other chemicals dissolves in water and reaches those nerve endings more quickly.

Another liquid that triggers your pain nerves in your tongue is soda. The carbon dioxide in the bubbles reacts with an enzyme in your mouth to form a weak chemical called carbonic acid. This acid fires the pain nerve endings in your tongue giving soda its “bite.”

How well can you tolerate this pain? Stick your tongue into a freshly opened glass of soda and hold it there. See how long you can keep it in the drink. One minute? Two minutes? Most people can’t last a minute. But maybe you’re tougher than that.

Some Mexican parents give their kids mixtures of sugar and red chili powder when they’re little to build up their tolerance for spicy foods. Do you think that people who love spicy food could also be champions at keeping their tongues immersed in soda? Design an experiment to find out at your next party.

Hot Stuff from Vicki Cobb on Vimeo.

atonguelashing from Vicki Cobb on Vimeo.

These videos were made from Vicki Cobb’s book We Dare You! She invites you to join her video project and make your own videos from her book and post them on the www.wedareyouvideos.com website.

Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Cobb, Vicki. "Some Painful Truth." Nonfiction Minute, iNK Think Tank, 17 Oct. 2017, www.nonfictionminute.org/the-nonfiction-minute/some-painful-truth.

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The Battle Hymn of the Chicken Pox Troopers

5/23/2022

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Vicki Cobb
The Master Chef of Kids’ Hands-on Science

How does a virus cause a disease? A virus is not a complete living thing. It is like a free-floating nucleus of cell. It doesn’t “grow” but under certain conditions it can make a copy of itself or reproduce. It invades the cells of other living things to use the internal structure of the host cells to reproduce. At a certain point, the number of new viruses in a cell is so large that the cell ruptures and dies, spilling out newly made viruses to continue the invasion to other uninfected cells.

One virus we understand very well is chicken pox. Chicken pox is a very contagious disease that enters the body through the air and affects mostly children. When I was young almost every kid got chicken pox but, since 1995, there has been a vaccine, which makes you immune and protects the spread of the disease to others. Is there another way to explain how this virus works? Suppose I imagine a virus could think, which it can’t. But, imagination gives me the freedom to think differently.

So I wrote a poem about an army of chicken pox viruses as they are about to attack a human being, maybe you, my reader. A “battle hymm” is a chant or a song to rally the troups just before an attack.

The Battle Hymn of the Chicken Pox Troopers

Charge forward, fellow viruses!
Invade a cell or two
Then let us join together
And make a chicken pox on you.

Let cells try to fight us
No matter what they do
Red spots of our graffiti
Make a chicken pox on you

We make the top skin separate
And fill the space with goo,
Small, itchy blisters are a stage
Of chicken pox on you.

And when the blisters break, my friend
You think perhaps we’re through
But no. Now there is a scab
For each chicken pox on you

Scratch a scab so it comes off
Baring skin that’s raw and new,
A scar forever marks the spot
Of that chicken pox on you.

The source? Chicken with fowl pox

To the battle, fellow viruses!
We’re more noteworthy than flu
They just make you feel sick
We make our chicken pox on you!

Meet your personal superheroes - your body's cells Superhero cells rally together to battle common childhood ailments in this series in which Vicki Cobb explains how your amazing human body heals itself and fights off intruders. Here's her book on yet another virus: Your Body Battles a Cold.

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Banging on the Ear Drum

5/16/2022

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Vicki Cobb

The Master Chef of kids’ hands-on science

Ever notice people wearing headsets to keep out noise? Check out the workers on the tarmac of airports, or gardeners with their leaf blowers, or road workers breaking up blacktop with a pneumatic drill. They wear these headsets to protect their ears from damage caused by persistent loud noise.

Loudness is measured in decibels, dB for short. Complete silence is 0 dB, a whisper is 10 dB, normal conversation is 60 dB or about 10,000 times louder than a whisper. A lawnmower is 90 dB, about 1,000 times louder than a conversation and a jet engine is 120 dB about 1,000,000 times louder than a conversation. Anything over 85 dB does damage to our ears. That’s because sound traveling through air is a force beating against delicate eardrums. Yes, rock concerts damage ears.

Performing musicians often have tiny earpieces in their ears. This way the sound engineers can send them the sounds of their own voices or instruments, so that they can hear themselves over the other musicians. Those pieces are not for protection. So the dB level of rock concerts can affect those musicians’ hearing. There is even a name for it: Noise Induced Hearing Loss or NIHL. Rock musicians are the top profession to suffer NIHL later in life.

But there is a new threat to hearing loss—the earbuds people use to listen to music from their electronic devices. They are fine if you keep the volume down. But if you’re hooked on loudness that invades all your senses so that you can’t “hear yourself think” and you listen for several hours a day, you’ll pay the price down the road.

Your ability to hear high tones is the first to go. Here’s a quick and easy hearing test you can use on yourself and your family: Turn on the TV and hit the “mute” button or turn the volume all the way down. Lean over the back of the set and listen for a very soft, high-pitched whine. If you can hear it, you are listening to the highest sound the human ear can hear. (Dogs, of course, can hear much higher sounds, hence the dog whistle, which people can’t hear but dogs can.) Walk away from the set to find the distance when you can no longer hear it. Do the same test with your parents. Bet your hearing is better than theirs.

Try listening to some old-fashioned, melodic, soft popular music that came before rock and roll. You just might like it.

Listening to her own soft music, or just blocking out your loud music? Either way, her hearing is better than yours. Photo by Alexandra Siy

From School Library Journal--
"Fun!" comes through loud and clear in this energetic exploration of hearing and auditory perception. Cobb gets the anatomy lesson out of the way, then moves on to a series of simple activities to help kids experiment with their own sense of hearing. Students investigate sound conduction, perception of pitch, echolocation, and range of hearing by doing such things as sticking fingers in their ears while they talk."
Available for download at the i-Tunes store -- click here.

Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Cobb, Vicki. "Banging on the Ear Drum." Nonfiction Minute, iNK Think Tank, 30
Apr. 2018, www.nonfictionminute.org/the-nonfiction-minute/Banging-on-the-Ear-Drum.

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Why You Can’t Defrost a Salad…Yet

5/2/2022

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Vicki Cobb
The Master Chef of Kids' Hands-on Science

At left in the back is a fresh spinach leaf that has been treated with trehalose, frozen and defrosted.. The droopy one has been frozen and defrosted without trehalose. It's what is giving us hope that we may soon be able to defrost a salad.

When it comes to preserving a fresh taste in food to be eaten at some later time, nothing beats freezing it. That was the discovery made by Clarence Birdseye in 1924. He had been working in northern Canada and noticed that fish caught by the native Canadian Inuits froze almost instantly in the frigid winter air. It was just as delicious when cooked and eaten months later as it was on the day it was fresh. Birdseye figured that if food was frozen quickly at very cold temperatures, large ice crystals couldn’t form to damage the food and make it mushy. His flash-freezing process made him very rich.

The problem isn’t so much the freezing of food as what happens when it’s defrosted. See for yourself. Stick a stalk of celery in your freezer. The next day defrost it. Want to eat it? Compare it to a fresh unfrozen stalk. The perky structure of fresh celery is destroyed by ice. Water has the very unusual property of expanding and taking up more space when it changes into ice than when in a liquid state. That’s why ice cubes float and frozen unopened soda cans bulge.   Expanding ice crystals destroy the cell walls of plants. Quickly freezing fresh food keeps the ice crystals smaller than slower freezing, but they are still large enough to destroy the cell walls of delicate vegetables like spinach or lettuce. But if you defrost frozen spinach from the supermarket it is beyond limp. So a salad you can defrost and serve as if it were fresh has seemed like an impossible dream.

Federico Gomez, a Swedish scientist, is working to change this. Like Birdseye he took a close look at nature, specifically at plants that stay alive in very cold climates. He discovered that they contain a sugar called trehalose (tree-HAL-ose) that works like a natural antifreeze. Could he find a way to get trehalose into spinach leaves? If so, would the trehalose protect the structure of the spinach and keep it crisp after defrosting? This picture shows the results. The leaf on the left was treated with trehalose. The one on the right was untreated. He froze and defrosted both. The treated leaf is as crisp as if it had never been frozen!

Just because there is success in a lab doesn’t mean a defrosted salad will show up on your dinner plate any time soon. But these results are enough to keep the research going.

Move over Clarence Birdseye!

This is a nice fresh, crisp piece of celery...

...and this is the same piece of celery after being frozen and then defrosted. Yuk!

Cobb has revised her classic book, Science Experiments You Can Eat. While doing her research, she came across this work of Frederico Gomez. She bought trehalose on line and soaked some slices of parsnip and zucchini in a trehalose solution, hoping that the sugar would be absorbed by the plant cells. But when she froze them and defrosted them, it didn't work. Dr. Gomez got the sugar inside the plant cells by removing some water from between the cells in a vacuum chamber, soaking the leaves in a trehalose solution (which moved the sugar into the spaces outside the cells) and then exposing the leaves with a mild electric shock to get the sugar through the cell walls. Vicki didn't have the equipment to do all this but she tried anyway. The book was published in 2016.

Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Cobb, Vicki. "Why You Can't Defrost a Salad...Yet." Nonfiction Minute, iNK Think
Tank, 11 01 2018, www.nonfictionminute.org/the-nonfiction-minute/
Why-You-Can't-Defrost-a-Salad-Yet.

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The Mystery of the Alternating Nostrils

Some Painful Truth

The Battle Hymn of the Chicken Pox Troopers

Banging on the Ear Drum

Why You Can’t Defrost a Salad…Yet

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