Why do we salivate before we vomit?

Thursday 24th September 2009
Submitted by Luis Villazon
NICOLA BAIN, GLASGOW

Vomiting is a deliberate response by the body that evolved as a purging mechanism to remove toxins or foreign bodies from the stomach and oesophagus. Since stomach contents are highly acidic, vomiting can be quite harmful for the throat, mouth and teeth and salivating helps to reduce this by diluting and rinsing. Saliva is also weakly alkaline, which helps to neutralise acid.

What's the fastest speed a human has ever experienced?
previous qanda Article
Do vinyl records really sound better than CDs?
next qanda Article
Q&A Tabs

Lots of insects hide in burrows and only emerge at night, or use camouflage to avoid detection. But, more than any other group of animals, insects are also masters of the opposite strategy called...

Mammals remove excess nitrogen from their bodies by converting it to a dilute solution of urea, stored in the bladder. Birds convert nitrogen to uric acid instead: this is metabolically more...

Phlegm is the mucous secretion of the respiratory passages. The cilia cells that line these passages are continually driving the phlegm upward to the throat, where it triggers the swallow reflex...

The powder is actually tiny scales made from modified hairs. Moths, like butterflies, belong to the order Lepidoptera, which means 'scale wing'. The scales are pigmented but they also contribute...

Lobsters and other shellfish have harmful bacteria naturally present in their flesh. Once the lobster is dead, these bacteria can rapidly multiply and release toxins that may not be destroyed by...

All female mammals have a clitoris, the sole purpose of which is to react to sexual stimulation, and presumably this stimulation has evolved to be pleasurable for most species. But establishing...

To create a sound, we have to set matter - whether it's a gas like air, a liquid or even a solid material - in regular motion, creating a wave of specific frequencies, which we hear as a sound of...

Mirrors don’t reverse left and right either – that’s just our interpretation of what happens. Your reflection in the mirror is actually reversed front to back – if you have...

Discovered by an American student named Gary Flandro in the mid-1960s, the slingshot manoeuvre usually involves spacecraft briefly 'coat-tailing' a planet orbiting the Sun, extracting some of the...

The ice disappears because the wind blows away water molecules that have evaporated or 'sublimed' from the ice, so the ice slowly shrinks in size. The molecules that escape are those with the...