A quiz day and you-facts

• How good are you at spotting fake smiles? "Most people are surprisingly bad at spotting fake smiles. One possible explanation for this is that it may be easier for people to get along if they don't always know what others are really feeling." Take the quiz here. I got 14 right out of 20.
• Burtyic acid is what makes your vomit smell disgusting. It is also found in Parmesan cheese. Take a sense quiz here.
• How does a growth spurt work? First, hands and feet expand. Next, arms and legs. The shins grow before the thighs, and the forearm grows before the upper arm. Clumsiness is caused as the brain tries to adjust to the new center of gravity. "[T]he relationship between growth of the skeleton and puberty is so strong that a teenager's developmental age can be measured by looking at the maturity of the bones in their hand and wrist. Source
• 1. "The average person will shed 40 pounds of skin in his/her lifetime."
• 2. "The human brain is composed of 75% water."
• 3. " A person produces 10,000 gallons of saliva in an average lifetime."
• 4. "A nail takes around 6 months to grow from base to the tip." Source