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Author Question: The earliest human societies could generally support no more than ___________ members. a. 10 b. ... (Read 42 times) |
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
According to research, pregnant women tend to eat more if carrying a baby boy. Male fetuses may secrete a chemical that stimulates their mothers to step up her energy intake.
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.
When blood is deoxygenated and flowing back to the heart through the veins, it is dark reddish-blue in color. Blood in the arteries that is oxygenated and flowing out to the body is bright red. Whereas arterial blood comes out in spurts, venous blood flows.
Approximately 15–25% of recognized pregnancies end in miscarriage. However, many miscarriages often occur before a woman even knows she is pregnant.