Which gas was the least abundant in the earth's atmosphere 3.5 billion years ago?
A. oxygen
B. nitrogen
C. carbon dioxide
D. carbon monoxide
Answer: A. oxygen
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There is a controversy over pre-teen girls receiving the HPV vaccine. Many parents think that giving this vaccine condones sexual activity at a young age. On the other hand, there are parents who do not want their kids to pick up STIs. Why is the vaccine recommended for 11-12 year old girls? Why not give the vaccine to young adult women who are just becoming sexually active?
A. Very young women tend to get cancer from HPV, whereas women who are older get warts from HPV. B. The immune system is strongest in pre-teen girls, so it is best to give the vaccine very early in life. C. Once the young woman becomes infected with HPV, the virus gets into cells. It is then too late to vaccinate. D. The vaccine is cheaper for young girls since the dosage of virus in the vaccine is far less than that given for older women.
Fever develops when ____ stimulate the brain to release prostaglandins
a. cytokines b. histamines c. interferons d. complement e. histamines
Which area has the highest nitrogen deposition?
A) East Coast B) West Coast C) South D) Midwest
A genomic library is a collection of ________ that contains DNA fragments representing most, if not all, of the genome of an organism
Fill in the blank with correct word.