Red-green color blindness affects about 1 in 12 men but only 1 in 200 women. The reason: the genes for the red- and green-sensitive pigments sit on the X chromosome. Men have just one, with no backup copy; women have two. For those affected, a ripe fruit and an unripe one can look almost identical.
Every day, your kidneys filter around 180 liters of blood plasma, about a bathtub's worth. Yet you only have about 3 liters of plasma, so it passes through your kidneys some sixty times a day. Over 99% of the filtered water is reabsorbed, leaving just one to two liters of urine.
A 70 kg adult is made of about 7 × 10²⁷ atoms, or seven billion billion billion. The observable universe is thought to hold on the order of 10²² to 10²⁴ stars. Even with the high estimate, you contain thousands of times more atoms than there are stars in the entire visible cosmos.