The mechanics of smell

LIFESTYLE NEWS - Smell occurs when an odour binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system.

Glomeruli - tiny blood vessels - aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input starts to interact with parts of the brain responsible for smell identification, memory, and emotion.

Sniffing out smelly facts

• Humans can smell one trillion different scents.

• Favourite smells include orange, vanilla, cinnamon and of course coffee! Do we hear beer?

• People, just like animals, can smell fear and then experience the same emotion.

• Men who have a few pints on the sly after work, know that they can't hide their little detour from their wives. Women have a more acute sense of smell than men. So, if your buddy says he can't smell beer on you, best ask a woman's opinion before heading home!

• Humans have five to six million odour-detecting cells. Dogs have 220 million cells.

• It is during exhalation that the smell's contribution to flavour occurs, in contrast to that of proper smell, which occurs during inhalation.

• Humans can detect blood relatives by smell. Mothers can identify their biological children by body odour but not their stepchildren. Pre-adolescent children can smell their full siblings but not half-siblings or step siblings, and this might explain incest avoidance.

• Just like fingerprints, every person has a unique distinct odour.

The human olfactory system. 1: Olfactory bulb 2: Mitral cells 3: Bone (Cribriform plate) 4: Nasal epithelium 5: Glomeruli 6: Olfactory receptor cells.

Sickly smells

• Viruses can infect the olfactory epithelium leading to loss of smell. About 50% of patients with SARS-CoV-2 (causing Covid-19) experience some type of disorder associated with their sense of smell. Sars-CoV-1, Mers-CoV and even the flu can disrupt our sense of smell.

• There's hope for long Covid sufferers who have lost their sense of smell. The cranial nerve responsible for smell is the only one that can regenerate.

• Loss of smell may signal future illnesses like Parkinson's disease and Alzheimer's.

Pooh, I can't bear it

Grizzly bears have a sense of smell seven times stronger than that of the best canine sniffer, the bloodhound. The bear's excellent sense of smell is essential for locating food underground.

They can detect the scent of food nearly 30 km away!

The smell of rain

Petrichor (/'p?tr?k??r/) is the earthy scent produced when rain falls on dry soil. The word is constructed from Greek petra (π?τρα), "rock", or petros (π?τρος), "stone"; and ichor (?χ?ρ), the fluid that flows in the veins of the gods in Greek mythology.

Smelly quiz

• Why are people with foot fetishes often losers?
They love the smell of defeat.

• Why does Piglet smell so bad?
Because he plays with Pooh.

• Why did the hoody smell like weed?
It was high fashion.

• What would happen if skunks didn't have their protective smell?
They would go ex-stinked.

Aromatic quotes

• Guests, like fish, begin to smell after three days. - Benjamin Franklin

• You're only here for a short visit. Don't hurry, don't worry. And be sure to smell the flowers along the way. - Walter Hagen

• What's in a name? That which we call a rose by any other name would smell as sweet. - William Shakespeare

• In the spring, at the end of the day, you should smell like dirt. - Margaret Atwood• A book has got smell. A new book smells great. An old book smells even better. An old book smells like ancient Egypt. - Ray Bradbury

The darn durian

According to sciencealert.com the notorious durian fruit from South East Asia can smell so bad that it has led to a massive evacuation at a University in Melbourne after students feared there was a gas leakage.

But it was only a rotten durian fruit's smell that got carried over the air conditioning.
According to a study, the durian fruit gets its smell from 44-odour active compounds that can smell like anything from a rotten egg to delicious caramel.

The smell of tears is a passion killer

According to smithsonianmag.com the sight of someone in tears might make you feel concerned. But the smell of tears, researchers say, has a different effect. Women's tears collected and placed under men's noses reduced the men's sexual arousal and testosterone levels. It seems tears sent a message that romance was not on the cards.

The smell of tears is a turn-off.
Photo: unsplash.com / Luis Galvez @louiscesar