TASTE AND SMELL http://www.livescience.com

OUR SENSE OF TASTE INSECTS HAVE THE MOST DEVELOPED SENSE OF TASTE-THEY HAVE TASTE SENSORS ON THEIR FEET, ANTENNAE AND MOUTHPARTS FISH CAN TASTE WITH THEIR FINS AND TAIL AS WELL AS THEIR MOUTHS WE ARE BORN WITH 10 000 TASTE BUDS INSIDE OUR MOUTHS. THEY ARE REPLACED EVERY TWO WEEKS IN HUMANS, FEMALES HAVE MORE TASTEBUDS THAN MALES TASTE IS THE WEAKEST OF THE 5 SENSES. AN “AVERAGE” TASTER HAS ABOUT 184 TASTE BUDS/cm2 SOME PEOPLE ARE “SUPERTASTERS” WITH 425 TASTE BUDS/cm2

WHEN YOU WERE A BABY, YOU HAD TASTE BUDS NOT ONLY ON YOUR TONGUE, BUT ALSO ON THE SIDES AND ROOF OF YOUR MOUTH. AS YOU GREW, THE TASTE BUDS BEGAN TO DISAPPEAR FROM THE SIDES AND ROOF OF YOUR MOUTH LEAVING TASTE BUDS MOSTLY ON YOUR TONGUE. AS YOU GET OLDER, YOUR TASTE BUDS WILL BECOME EVEN LESS SENSITIVE SMOKING CAN REDUCE THE NUMBER OF TASTE BUDS. CERTAIN MEDICINES, VITAMIN DEFICIENCY, HEAD TRAUMA, EXPOSURE TO CHEMICALS AND RADIATION CAN ALSO AFFECT YOUR SENSE OF TASTE.

THE TOP OF YOUR TONGUE IS COVERED WITH A LAYER OF BUMPS CALLED PAPILLAE. PAPILLAE HELP GRIP FOOD AND MOVE IT AROUND WHILE YOU CHEW. AND THEY CONTAIN THE TASTE BUDS.

EACH TASTE BUD IS MADE UP OF TASTE CELLS, WHICH HAVE SENSITIVE, MICROSCOPIC HAIRS CALLED MICROVILLI. THOSE TINY HAIRS SEND MESSAGES TO THE BRAIN, WHICH INTERPRETS THE SIGNALS AND IDENTIFIES THE TASTE FOR YOU.

THE TONGUE IS NOT THE ONLY THING THAT 'TASTES' YOUR FOOD. THE NOSE IS HELPING ALSO. THE TONGUE AND NOSE WORK TOGETHER. MOLECULES OF FOOD STIMULATE THE TASTE CELLS TO SEND MESSAGES TO YOUR BRAIN. TASTE BUDS CAN DETECT SWEET, SOUR, BITTER AND SALTY FLAVOURS. PS- a new taste has been identified-it is called “umami” FOR A LONG TIME THIS MAP OF TASTE BUDS WAS ACCEPTED AS BEING TRUE SCIENTISTS HAVE NOW PROVEN THAT THIS IS INCORRECT-THE TONGUE IS ABLE TO SENSE ALL THESE TASTES MORE OR LESS EQUALLY.

OUR SENSE OF SMELL THE NOSE LETS US SMELL AND IT'S A BIG PART OF WHY WE ARE ABLE TO TASTE THINGS. THE SENSE OF SMELL BRINGS US INTO HARMONY WITH NATURE, WARNS US OF DANGERS AND SHARPENS OUR AWARENESS OF OTHER PEOPLE, PLACES AND THINGS. BABIES RECOGNIZE THE SMELL OF THEIR MOTHER IMMEDIATELY. IT IS THE FIRST CONTACT OF THE BABY WITH THE OUTSIDE WORLD. NO TWO PEOPLE HAVE THE EXACT SAME ODOUR OR “SMELL FINGERPRINT” WHICH IS DETERMINED BY MANY FACTORS INCLUDING: OUR GENES, SKIN TYPE, DIET, MEDICINE, MOOD STATE AND EVEN THE WEATHER.

THERE ARE 10 MILLION ODOUR RECEPTORS IN THE NOSE. IDENTIFYING SMELLS IS THE BRAIN'S WAY OF TELLING ABOUT THE ENVIRONMENT. YOUR SENSE OF SMELL ALSO CAN HELP YOU KEEP SAFE. IT CAN WARN YOU NOT TO EAT SOMETHING THAT SMELLS ROTTEN OR HELP YOU DETECT SMOKE BEFORE YOU SEE A FIRE. THE AVERAGE HUMAN BEING IS ABLE TO RECOGNIZE APPROXIMATELY 10,000 DIFFERENT ODOURS. DOGS HAVE ABOUT 200 MILLION OLFACTORY RECEPTORS. THAT IS ABOUT 20 TIMES THE NUMBER OF RECEPTORS THAT HUMANS HAVE.

SMELL AND TASTE ARE CLOSELY LINKED SMELL AND TASTE ARE CLOSELY LINKED. THE TASTE BUDS OF THE TONGUE IDENTIFY TASTE; THE NERVES IN THE NOSE IDENTIFY THE SMELL. BOTH SENSATIONS ARE COMMUNICATED TO THE BRAIN, WHICH COMBINES THE INFORMATION SO THAT FLAVOURS CAN BE RECOGNIZED AND APPRECIATED.

CAN YOU REMEMBER? HOW MANY TASTE BUDS YOU ARE BORN WITH? 2. HOW OFTEN THEY ARE REPLACED? 3. WHAT FACTORS CAN AFFECT OUR SENSE OF TASTE? 4. WHAT HAPPENS TO OUR SENSE OF TASTE AS WE GET OLDER? 5. WHAT ARE THE MAJOR TASTES WE CAN DETECT? 6. HOW MANY ODOUR RECEPTORS ARE THERE IN AN AVERAGE HUMAN NOSE? 7. HOW DO OUR SENSES OF TASTE AND SMELL HELP US?