Author Archives: carole

Scurvy!

One of our favorite dress up games is playing Pirate. Pirates get all the cool sayings, like “Yo ho ho” and “ARRRR!” and “Scurvy knaves!” We didn’t realize scurvy was a “thing” until we saw this video on “Spongebob Squarepants”

Spots on your back and teeth falling out? Gross! And what’s that stuff about a lemon tree?

Turns out scurvy is a real disease, and spots on your skin and spongy gums (EWW!) are two of the symptoms. It happens when you don’t get enough vitamin C. Long ago pirates and other sailors who were at sea for long periods had to live off preserved foods like dried meats. They didn’t get many fruits and vegetables, and so they would develop the kinds of health problems like scurvy that happen when you don’t eat a variety of good healthy foods.

Scurvy is pretty rare in modern times. Eating a variety of fruits (especially citrus fruits like oranges and lemons) and vegetables helps, and so does taking a vitamin C supplement. Drink your orange juice and you won’t have to worry about being a “scurvy knave”!

All About Copper!

Last weekend we were looking at the steeple of a church. It was sort of a green mottled color. We found out it was made of copper. Pennies are made of copper too—why is the penny a brownish-reddish color and the church steeple is green?

The Statue of Liberty

The Statue of Liberty

When copper is exposed to oxygen in the air, there is a chemical reaction that turns it green. It takes years for the copper to turn from the coppery metallic color to the greenish-bluish color. Did you know that the Statue of Liberty is made of copper?

So why don’t pennies turn green? Well, being in people’s pockets, change purses, and in people’s hands, rather than exposed to the air like the church steeple helps. And pennies aren’t pure copper. Pennies are made from an alloy (mixture) of copper and zinc.

Copper is an element. Elements are the basic building blocks of… well, everything! Combined together, elements form chemical compounds. This video from our new favorite album “Here Comes Science” is about the periodic table, which lists all the elements:

Where Does Mold Come From?

moldy_tomatoAfter switching lunchboxes, we kind of forgot the old one for a while. And the half of a bagel with cream cheese that was inside. Oops.

Opening up the old lunchbox, we saw a lot of green fuzzy stuff—mold – had grown on the outside of the bagel.

What makes mold grow? What is mold, anyway?

Mold is a living microorganism that is part of the Fungi kingdom. Fungi aren’t plants, and they aren’t animals. Yeasts (used to make bread rise) and mushrooms are fungi, too. Fungi “eat” by releasing enzymes that break down their food into a form the fungi can absorb.

How did the mold get on the bagel? Mold reproduces by releasing tiny spores. These spores are so small that they can float in the air, from food source to food source. Mold grows well in moist conditions, which is why some foods, like fruit, attract it more than others. Molds come in many different colors, from black to blue to green.

Mold may look gross, it may be hard to clean up, and it may even cause allergies and breathing problems in some people, but mold isn’t all bad. There are quite a few medicines made from mold, including penicillin, which is used to treat illnesses like strep throat. Mold is even used to produce some kinds of food, like soy sauce and certain types of cheese. Fungi of all sorts are important in helping decompose (break down) organic matter.

Speaking of fungi, here’s an unscientific* joke for you:

Q: Why did all the girl mushrooms want to date the guy mushroom?
A. Because they knew that he was a fungi! (Get it? A fun guy!)

*This joke is unscientific because we know that fungi are asexual—there are no girl and no boy mushrooms!

Bay Bridge Construction

The San Francisco-Oakland Bay Bridge is closed this weekend for a major project, part of the seismic upgrade of the bridge. This will make the bridge safer in case of a major earthquake.

In 1989, the Loma Prieta Earthquake damaged a 50-foot section of the upper deck on the Eastern side, making it collapse onto the lower deck. This weekend’s project is part of a major construction project that will eventually replace the Eastern span of the bridge, scheduled for completion in 2013.

We’re watching the construction crews in action on the construction cams. There’s a cool computer simulation of the work that is being done this weekend, and when the job is done, all the video that is being shot will be available in a time-lapse video on http://baybridgeinfo.org.

Musical Minds

Oliver Sacks We can’t stop thinking about an episode of the PBS show “Nova” we watched a couple weeks ago called “Musical Minds”. Oliver Sacks is a famous neurologist, a doctor who specializes in treating the body’s brain and nervous system. In “Musical Minds”, he talked with a young autistic man who is a brilliant piano player, a man with Tourette Syndrome whose symptoms stop when he plays the drums, and a woman who just heard noise when someone played music for her. The coolest story was about the man who got hit by lightning and suddenly was able to play beautiful music for the first time in his life.

You can watch a video clip, read a transcript of the show, and see Dr. Sacks’ answers to viewer questions on PBS.org, a great site for kid scientists to get information!

Photo credit: Mars Hill Church Seattle

Mythbusters Rule!

adam and jamie

One of our favorite shows is Mythbusters on The Discovery Channel. If you haven’t seen it, the guys (and Kari!) test a few urban myths and legends each week (like, would a house full of exploding popcorn make the windows bust out?) and proclaim them “Confirmed” or “Busted”. If you don’t get The Discovery Channel, you can see some videos here.

As big Mythbusters fans, we really had fun reading Geek Dad’s “Everything I Know About Parenting I Learned from Mythbusters“. “If It’s Worth Doing, It’s Worth Overdoing” sounds pretty familiar to us!

We got to see Adam and Jamie in San Francisco a couple of years ago, which is where the picture above was taken.

Ouch, Sunburn!

We went to the beach last weekend and got a sunburn on a spot we missed with sunscreen. What causes sunburn, and how does sunscreen help stop sunburns from happening?

When you’re outside, your skin is exposed to ultraviolet radiation (sometimes called UV radiation) from the sun’s rays. Even on cloudy days! Covering up your skin with long sleeves or a hat can help protect it from UV radiation and sunburn. Sunburns can be really painful, and can cause some types of skin cancer if you get too many of them in your lifetime. Some of the more common effects of a sunburn are redness, itchiness, and peeling skin. Your skin literally dries up and peels off! (EW!) Really bad sunburns, like other kinds of burns, can give you blisters on your skin.

Your skin has melanin, or pigment, that gives it color and protects it. You notice that the color of the skin on your arms is different from your friends, or even your brothers and sisters and mom or dad. If you have very pale skin, especially if you have freckles, you will be more likely to get a sunburn when you’re out in the sun. People with darker skin have more melanin. When they’re in the sun their skin may get a little darker and they’ll get a suntan. Many doctors say that even a little suntan is too much, and advise you to always wear sunscreen and a hat when you’re going to be in the sun for long periods.

Sunscreen coats your skin and blocks out the ultraviolet rays of the sun. Your bottle of sunscreen probably lists its “SPF” or “Sun Protection Factor”. The higher the SPF, the more protection it gives. Many sunscreens for kids have an SPF of 50 or higher. You need to apply more sunscreen after you’ve been swimming or if you’re sweating a lot. Staying out of the sun between 10 a.m. and 2 p.m. will reduce your risk of sunburn.

What do Sharks Eat? Everything!

We love the Academy of Sciences in Golden Gate Park. It has a planetarium, an indoor rain forest, and a wonderful underground aquarium with fish from all over the world.

The living fish exhibits are terrific, but this display really got our attention.
stomach_contentsIt shows the contents of a tiger shark’s stomach. There are turtle shells, a shoe, a license plate, an unopened can of Spam (not that a shark could open a can of Spam if he tried), and even two Barbie dolls!

Most sharks go after food that is easiest to catch, like slow, weak or dying marine animals. Sharks use their teeth to grab and tear their prey, but they don’t chew it up and usually swallow it almost whole. Many species of shark are bottom feeders, meaning they literally scoop up food from the bottom of the ocean. According to Seaworld.org, tiger sharks are the “garbage cans of the sea” because they will eat whatever is available. From the looks of this picture, we’d say that was a good description!

What the Heck is an Owl Pellet?

Our class went on a field trip to our local Science Center. We got to see lots of nature displays, but our favorite was the one about owl pellets. We even got to take some owl pellets home.

Owls are birds of prey, which means they hunt and eat small animals like mice. Owls can’t chew, though. They have to tear their prey into smaller pieces with their beaks and talons (claws) before they swallow them. One part of the owl’s stomach is called the proventriculus, or glandular stomach. That’s the part of the stomach that digests the parts of the prey the owl uses as food. The parts of the prey that the owl can’t digest, like bones, teeth, and fur, stay in the owl’s gizzard, or muscular stomach.

An owl pellet is the compressed (smooshed together) bones, teeth and fur of its prey. The owl regurgitates the pellet. It’s not like throwing up, though. The owl does this regularly, and the pellet just drops out of its beak.

We dissected owl pellets at the science center, and this is what we saw. owl_pellets1 It’s a little fuzzy, but you can see a bone, some teeth, and some fur. A little icky, but definitely interesting. Owls have to eat, too, you know.

What Do a Chicken Pox Shot and a Boxer Have in Common?

Not long ago, we had to have a vaccination for chicken pox. Another word for vaccination is immunization. It is usually given to you by your doctor in a needle (also called a shot), and we were a little scared. It helped to know why we needed the shot.

polio_vaccination_in_sweden_1957A vaccine is usually a weak form of a virus, like chicken pox or measles. When your body detects the virus your body’s immune system learns how to fight it off, so if you’re exposed to the disease later you don’t catch it and get sick. Your body has already fought it off!

Chicken pox is one of a number of diseases that used to be common childhood diseases. Even a mild case would make you feverish and itchy for days and days. We definitely wouldn’t want to go through that! Vaccinations have helped eliminate diseases like polio, which used to be common and were very dangerous.

We think the way a vaccination works to help your body fight off disease sounds a lot like a boxer training for a fight. A boxer starts training by working out and punching a punching bag, and pretty soon he is strong enough to knock out another boxer with one punch!

Photo credit: Wikimedia Commons