|
|
Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.
There are approximately 3 million unintended pregnancies in the United States each year.
People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.
Only 12 hours after an egg cell is fertilized by a sperm cell, the egg cell starts to divide. As it continues to divide, it moves along the fallopian tube toward the uterus at about 1 inch per day.
Hyperthyroidism leads to an increased rate of metabolism and affects about 1% of women but only 0.1% of men. For most people, this increased metabolic rate causes the thyroid gland to become enlarged (known as a goiter).
![The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that](https://biology-forums.com/gallery/47/medium_12359_29_04_12_6_05_04.jpeg)
![The meninges. This figure illustrates the location and structure of each layer of the meninges and t](https://biology-forums.com/gallery/47/medium_14755_27_08_12_4_56_12_8217900.jpeg)