I don't fear death so much as I fear its prologues: loneliness, decrepitude, pain, debilitation, depression, senility. After a few years of those, I imagine death presents like a holiday at the beach.

Saliva has antibacterial properties. It also has things called nerve growth factor, skin growth factor, histatins which help with wound closure. So when you see an animal licking a wound or even a mom kissing a child's boo-boo, there's some, there's some good science behind why one might do this.

In 'Packing for Mars,' I tried to convey the importance of getting young people interested in science.

I don't read good books anymore, it seems; I just buy them and put them on the shelf and every now and then walk over and pet them. I'm like the optimistic dieter who fills her closet with clothes two sizes too small and dreams of the day she can wear them. I know just what I want to do when I retire.

To keep your he-man jaw muscles from smashing your precious teeth, the only set you have, the body evolved an automated braking system faster and more sophisticated than anything on a Lexus. The jaw knows its own strength. The faster and more recklessly you close your mouth, the less force the muscles are willing to apply.

I used to do my best thinking while staring out airplane windows. The seat-back video system put a stop to that. Now I sit and watch old' Friends' and 'Everybody Loves Raymond' episodes. Walking is good, but here again, technology has interfered. I like to listen to iTunes while I walk home. I guess I don't think anymore.

Science is you! It's your head, it's your dog, it's your iPhone - it's the world. How do you see that as boring? If it's boring, it's because you're learning it from a textbook.

My books are not really books; they're endless chains of distraction shoved inside a cover. Many of them begin at the search box of Pub Med, an Internet database of medical journal articles.

I don't write on topics that require a lot of urgency. But in 'Stiff,' I wanted to change people's hearts about organ donation. Whenever I get a chance, I try to talk about that.

Pet foods come in a variety of flavors because that's what humans like, and we assume our pets like what we like. We're wrong.

Weightlessness was unbelievable. It's physical euphoria: Nothing about you has any weight. You don't realize that you are weighed down all the time by yourself, and your organs, and your head. Your arms weigh down your shoulders. In space simulation, you get to fly like Superman! You're hanging in the air! It's the coolest thing.

Picking my topics is sort of a process of elimination for me. Most things don't work for me. I like to cover science and unexpected things happening in labs. Also, theoretical research doesn't work for my style. I need scenes and interactions. Then, humor. I'm having the most fun when I can have fun with my work.

Every now and then, someone will tell me that one of my books has made them laugh out loud. I never believe them because: a.) my books don't make me laugh out loud; and b.) sometimes I have said this to a writer, when really what I meant was, 'Your book made me smile appreciatively.'