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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
The lipid bilayer is made of phospholipids. They are arranged in a double layer because one of their ends is attracted to water while the other is repelled by water.
Amoebae are the simplest type of protozoans, and are characterized by a feeding and dividing trophozoite stage that moves by temporary extensions called pseudopodia or false feet.
Blood is approximately twice as thick as water because of the cells and other components found in it.
The oldest recorded age was 122. Madame Jeanne Calment was born in France in 1875 and died in 1997. She was a vegetarian and loved olive oil, port wine, and chocolate.
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