Over the past 20 years, I have presented many science programmes on BBC1. But none is, I think, more socially important, or of more human interest, than this ongoing series of 'Child of Our Time.'

I did not study science at school until I was 13, when I was totally turned on by a seemingly dreary old teacher who suddenly, unannounced, manufactured a huge explosion in the middle of a totally boring monologue. From then on, all of his class wanted to make explosions.

Whether you're religious or not, there is a real need for other people's religious positions to be treated with the upmost respect.

To build and strengthen new connections, the brain needs the challenge of fresh and unusual stimuli. .... There's a lot of evidence to suggest that repetition is bad for brain health, and novelty is good.

Carbon dioxide is unusual because it doesn't go through the usual three phases of matter, from solid to liquid to gas, but it goes straight from solid to gas. The volume of the gas is much greater than the volume of the solid. When a solid turns into a gas, we say it sublimes. The process is sublimation.

In prehistoric times, Homo sapiens was deeply endangered. Early humans were less fleet of foot, with fewer natural weapons and less well-honed senses than all the predators that threatened them. Moreover, they were hampered in their movements by the need to protect their uniquely immature young - juicy meals for any hungry beast.

There needs to be clearer communication for the public avout how valuable it [animal testing] is