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Ask Dr. Universe bacteria

What is the most poisonous thing in the world? – Macmillan, 16, India

Dear Macmillan,

There are some amazing deadly things out there. Like a frog that oozes poison from its skin. Or a jellyfish that uses itty bitty hooks to inject venom into its prey.

But it turns out the most poisonous thing on Earth is everywhere. It’s in our soil. It’s in our water. It might be in your kitchen.

It’s a species of bacteria called Clostridium botulinum.

I talked about it with my friend Susie Craig. She studies food safety at Washington State University.

She told me that C. botulinum makes the toxin that causes botulism. People can get it by eating … » More …

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Why do we have germs on our hands? – Prince, 12, Georgia

Dear Prince,

Germs are tiny organisms—also called microbes. They’re so small you have to zoom in with a microscope to see them. They can be bacteria, viruses, fungi or other teeny things. Some microbes make us sick. Some don’t bother us at all. Some help us out.

I talked about all that with my friend Eric Lofgren. He studies infectious disease at Washington State University.

He said there are two main reasons we have germs on our skin. We pick up some microbes from the environment. Some live on our skin all the time.

“The world is full of microbes,” Lofgren said. “They’re very … » More …

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How do people get ear infections? – Lydia, 9, Illinois

Dear Lydia,

Ear infections aren’t fun. They can make your ears hot, itchy or painful. They can cause lots of pressure or make it harder to hear. Sometimes fluid leaks out of your ear.

I asked my friend Bevan Briggs why that happens. He’s a nurse practitioner and professor at Washington State University.

He told me people usually get outer ear or middle ear infections.

Your outer ear includes the flappy part attached to your head—called the auricle or pinna. It also includes the ear canal. That’s the tunnel that goes into your head. At the end of the ear canal, there’s a thin, flexible barrier of tissue called the eardrum. That’s the boundary between your outer ear and your middle ear.

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Why do you get acne? – Joey, 12, Illinois

Dear Joey,

Whether we call them pimples, spots or zits, acne is something most people experience. As many as 95% of people have some acne sometime. That’s nearly everybody.

I talked about acne with my friend Sarah Fincham. She has a clinical doctorate in nursing. She’s a nurse and a professor in the College of Nursing at Washington State University.

If you look at your skin, you’ll see tiny openings called pores. These pores connect to oil-producing glands under our skin. They’re called sebaceous glands, and the oil they make is called sebum.

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What are microorganisms? –Trystan, 11, North Carolina

Dear Trystan,

One of my favorite things to do is look at pond water with a microscope. I love to see all the teeny tiny critters zooming around in a single drop.

I talked about microorganisms, also called microbes, with my friend Claire Burbick. She’s a microbiologist at Washington State University. She told me the key trait for microbes is size. Microbes are micro—which means extremely small.

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