Human Body — Page 5
The incredible human body
267 facts
The human brain is the organ with the highest percentage of fat in the body.
About 60 per cent of the human brain is made up of fat. It is the fattiest organ in the human body. Fat is essential…
Babies are born with about 300 bones, but adults have only 206.
Babies are born with about 300 bones, many of which are cartilage. During growth, some bones fuse together. That is…
The nails on the dominant hand grow faster than those on the other hand.
The nails on the dominant hand grow faster because that hand is used more often, which increases blood circulation…
The acid in the human stomach is capable of dissolving a metal blade.
The hydrochloric acid in the stomach has a pH between 1 and 2, strong enough to dissolve a razor blade in about 24…
It is impossible to sneeze with your eyes open.
Sneezes are involuntary and involve a muscular contraction that includes the eyelid muscles. This neurological…
The human body emits as much heat as a 100-watt incandescent bulb.
At rest, the human body produces about 100 watts of thermal power, equivalent to a 100-watt incandescent bulb. This…
Human venous blood is not blue, but dark red.
Venous blood is often depicted as blue in books, but it is actually dark red. The bluish colour we see in veins is…
Hiccups are caused by the involuntary contraction of the liver.
Hiccups are caused by the involuntary contraction of the diaphragm, the muscle that separates the chest from the…
The bone marrow produces about 500 billion blood cells per day.
The bone marrow produces about 500 billion blood cells per day, including red blood cells, white blood cells and…
Humans lose about 100 hairs per day.
Humans lose between 50 and 100 hairs per day, on average. Hair grows about 1.25 centimetres per month and each…
Tooth enamel is the hardest substance in the human body.
Tooth enamel is the hardest substance in the human body, with a hardness of 5 on the Mohs scale. It is made of…
The human body produces about 1.5 litres of saliva per day.
The salivary glands produce between 1 and 1.5 litres of saliva per day. Saliva helps digest food, lubricate the mouth…
Nerve impulses travel at about 1 kilometre per hour.
Nerve impulses travel at speeds between 1 and 400 kilometres per hour, depending on the type of nerve and the…
The fat in the human body would be enough to make about 7 bars of soap.
The average adult human body contains about 16 percent fat, equivalent to approximately 10 to 12 kilograms. This…
We are shorter in the morning than at night.
We are about 1 to 2 centimetres taller when we wake up than when we go to bed. During the day, the body's weight…
The spleen can be removed without the person dying.
The spleen plays a role in filtering blood and immune defence, but it can be surgically removed. After removal, the…
The gallbladder can be removed without serious consequences.
The gallbladder stores bile produced by the liver, but it can be surgically removed. After removal, the liver…
The fingers have unique fingerprints, but the toes do not.
The toes also have unique prints, as do the palms of the hands and the soles of the feet. All these surfaces have…
The hyoid bone is the only bone in the human body not connected to other bones.
The hyoid bone, located in the throat, is not directly attached to any other bone. It is suspended by muscles and…
Humans have a vestigial bone called the tailbone.
The tailbone, or coccyx, is the vestige of a tail that our ancestors had. Although it no longer serves that purpose…
Humans are the only primate with a true chin.
Humans are the only primates with a prominent bony chin. Other primates, such as chimpanzees and gorillas, do not…
The human body contains enough phosphorus to make about 2,200 match heads.
The adult human body contains about 780 grams of phosphorus, most of it in bones and teeth. This amount would be…
The human body contains enough potassium to fire a toy cannon.
The adult human body contains about 140 grams of potassium, essential for muscle and nerve function. This amount…
The human body contains enough sulfur to kill all the fleas on a dog.
The adult human body contains about 140 grams of sulfur, present in amino acids such as cysteine and methionine. This…