In 1948, a man called Gustav Fechner thought that plants had emotions, so talking tot hem would help you get in touch with your plants and encourage them to grow. Studies also show that music might help plants, especially classical music. However, rock music is supposed to make plants wither away. But apparently this is not the case. If you talk to your plants, you're giving them lots of attention and probably looking after them a lot better. There's also some scientific truth in it. If you got right up close to your plants and talked to them for several hours a day, they'd probably get more carbon dioxide.

The way fluorescent lights work is that they contain gas at a certain low pressure, and you fire that gas up by putting a high frequency electrical signal through there. The electricity passing a current through the gas excites the atoms and they lose some of their electrons. The electrons are flicked up to a higher energy level, and then they fall back again to a normal energy level. When they do so, they emit some UV light, which strikes a phosphor, which is on the inside of the tube. That phosphor turns those UV rays into a second form of energy, which is visible white light. This process is very efficient. Tungsten light bulbs work by heating up a piece of metal in a tiny filament until it becomes white hot. Only about 20% of anything they actually use is turned into anything useful.

Fuel is different between winter and summer because the conditions it is used in are different. The starting conditions are particularly different, as engines have to get going from a much lower temperature. What you can do to winter fuel is add chemicals that make the petrol vaporise at a lower temperature, which facilitates cold starting. Using a better mix makes it easier for your car to start on a very cold day.

That's a really interesting question, and it explains why humans are different from things like amphibians. If you cut the tail off a newt, newts can grow back their tails and their limbs. But human cells can't do this, mostly. We do have some cells within our bodies such as in our brain and cells in our skin that do keep on growing. That's why we can heal small wounds. But with something like a finger, there are so many different types of complicated cells, that our stem cells are not capable of making them. They just don't have it left in them to do it. We basically don't have the genes and genetic programme to do it.

Yes, saliva does have some beneficial properties because it contains a number of proteins. Those proteins include antibodies, and we make a lot of antibodies when we are infected with various things, and they can mop up bugs and viruses. That's one bonus of saliva. It also contains another protein called lysozyme, and this is an enzyme that can break down some types of bacterial cell walls. When you lick something that has bacteria on it, those lysozymes attack the bacteria and help to neutralise them. Antibodies and lysozyme are also in your tears. Also in your saliva is mucus. Mucus is a protein that forms a sort of meshwork, and it traps things and stops them moving away too fast. So yes, saliva does have a medicinal role too.

The flu is a nasty virus. It tends to make mistakes when it copies itself, so that when the virus made in one person is passed onto someone else, it is slightly different to the one you were infected with. As the flu goes around the world every year, by the time it's got back to where it started, it looks very different from the version that was here before. When you get the flu the next year, your immune system cannot recognise it because it looks completely different. So a vaccine is only good until the flu changes, which is why you have to have a new jab every year.

I think if you're small animal, it's quite hard not to fall over. So if you have a large number of legs you can stay on the ground more of the time. So essentially, insects have more legs than humans because if they had less legs, they would fall over very easily.

Actually rheumatoid arthritis is the immune system attacking joint tissue, which it shouldn't do. So it's the immune system going out of control. I don't think it would do him any harm at all. Whether it would do him any good, I couldn't really say. There have been many claims made, but not many have been substantiated I don't think.

In a single stretch, I probably think it's the dragonfly. These animals spend most of their life on the wing and they just come down to settle to look to see where the prey is. They can fly for quite long periods. There are many insects that have been found several hundred miles off of the coast, so lots of things can fly for long distances if they get caught by the wind. I think the insect that can fly the furthest under its own steam is probably the little biting black flies, which you get in West Africa. They can do 300 kilometres while looking for prey. The most famous migrating insect is the monarch butterfly, which flies across North America to special roosting sites in Mexico. That's a very famous, powerfully flying migrating butterfly.