|
Author Question: The use of selective breeding in human agriculture: a. is a very recent scientific concept. b. ... (Read 14 times) |
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Chronic marijuana use can damage the white blood cells and reduce the immune system's ability to respond to disease by as much as 40%. Without a strong immune system, the body is vulnerable to all kinds of degenerative and infectious diseases.
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.