Does 100 % of oxygen come from trees?

That is a great question! Humans need oxygen to live, so it’s a good idea to know where it comes from. Oxygen is released into the air by trees but it can also be found in lots of other places.

Oxygen makes up about 20% of air, and it is also found in water. It is also found in rocks, minerals, plants, and the human body. Oxygen is needed for fires, and it is essential for humans to breathe. The oxygen in the air also has another form known as ozone. Ozone makes up part of the atmosphere known as the ozone layer and protects the Earth from harmful ultraviolet rays.

Oxygen is produced by some kinds of bacteria, algae, and plants (including trees) during photosynthesis. Photosynthesis is the process by which bacteria, algae, and... Keep reading.

What causes the electrical shock I receive when getting out of a car during the winter? Vicello (age 36)

The shock you get when getting out of your car, particularly in the winter, is from static electricity. Static electricity often occurs whenever two dissimilar materials are rubbed together. When electrons, or the negative charge, are removed from one material and deposited on the other a static charge results. When you are in a car the seat is one material and your clothes are another when you move you create friction and build up a static charge. Once your body accumulates enough of a charge and then touches a good conductor, usually metal like the car door the charge quickly leaves you and you feel the shock.

The reason you feel this shock more in the winter than in the... Keep reading.

Are bones living or dead? (age 9)

That is a good question. When you see an example of bone, you often see it as white, hard and lifeless. It almost looks rock-like. Bones look this way because of the way they have been preserved, usually bleached and dried out. In fact, bones, like all other tissues in your body are alive. Because bones are the main support structure for us, they are made of a hard material that is mainly calcium. Throughout this hard substance, are blood vessels and nerves. Blood is the body’s transport system, bringing nutrients and oxygen while taking away waste products. Anything that is alive in the body needs these things to nourish it. If your bones did not have these blood vessels in the bone, you would be in trouble if you had a broken bone. Often when... Keep reading.

When someone has chapped lips and they put on chapstick their lips heal within a few days. What is in chapstick that makes our lips heal so quickly? (age 11)

The answer to this question has to do with the skin on our lips. If you look closely at your lips, you can see that there isn’t any hair on the pink part of your lips. Your lips also don’t have sweat glands or oil glands like other areas of your skin. On the rest of your body, the hair, sweat, and oil protect your skin. Since your lips don’t have this protection, they dry out more easily. When they dry out, they get chapped. Sun exposure, wind, dry weather, and licking your lips can all make your lips dry and chapped. When you put lip balm on your lips, it acts like the oils on other parts of your skin. The lip... Keep reading.

I got a fire bellied frog for Christmas and we know they carry toxins, does that mean I can never touch my frog? Is there any way I can play with it? (Sonia)

Sonia,

The fire bellied toad, Bombina orientalis, is not a threat to you or any other person if proper basic care is given to the animal. The toxins produced by the toad are almost never irritating to the skin but can be irritating to mucous membranes (including your eyes) and bodily orifices. As long as your hands are washed before and after handling the animal you will be safe.

Handling amphibians however is not safe for the animal. Oils found on human skin have a negative effect on the animal’s skin. Amphibian skin is an important part of its respiratory system. The animal’s moist skin actually helps with gas... Keep reading.