Welcome to this Friday's round-up of the week's top questions on The Last Word.

Questions this week have been overwhelmingly biological. Today, we're wondering what is happening to symphylan's tastebuds. When drinking well water after chlorinated water, symphylan experiences a strange bitter taste. Can you explain these tastebud troubles?

For a bit of entomology, Alisong found a 5.5-centimetre-long moth on her gatepost. There's been quite a discussion about it - take a look to find out what it is, or add more heat to the debate.

This one's not for the faint-hearted, but it's pretty egg-citing: take a look at what's hiding in the white of these chickens' eggs.

Ed_Harman was puzzled by his ability to sleep until exactly midday every day, irrespective of the time he goes to bed. Some of our Last Worders help explain why he awakes at the same time every day.

The exception to the biological theme was celliottuk's question: if you want to stop fizzy drinks from going flat, would it help to squash the bottles that contain them?The Last Word members strike again with explanations of what gaseous shenanigans are going on in those bottles.

If you have a better answer for any of this week's questions, roll up your sleeves and get stuck in. Otherwise, sit back and enjoy the explanations!

All the best,

Kat

Letters and comments editor, New Scientist