|
|
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Approximately 500,000 babies are born each year in the United States to teenage mothers.
Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.
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.
The average adult has about 21 square feet of skin.