A lack of ozone is dangerous because ozone
A. cools the Earth.
B. filters out dangerous ultraviolet rays.
C. triggers the development of clouds.
D. is a reserve for oxygen that we breathe.
Answer: B
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Dosage compensation refers to the fact that:
A. the level of expression for a given gene is directly related to the number of copies of the gene. B. genes on the Y chromosome must be expressed at higher levels than would otherwise be the case because they are not homologous with genes on the X chromosome. C. genes on the X chromosome must be expressed at lower levels than would otherwise be the case because they are not homologous with genes on the Y chromosome. D. X chromosome genes must be regulated differently in males and females because members of one sex have 2 X chromosomes, whereas members of the other have only 1. E. None of these choices are correct.
Bob dreamt he was biking for five hours. The actual time he was in ____ sleep was about ____ min
a. beta; 15?20 b. EEG; 10?15 c. REM; 60?90 d. REM; 10?15 e. EEG; 90
What is the function of the prostate secretions?
a. sperm maturation b. to provide sperm with energy c. to protect sperm from vaginal acidity d. to stimulate the release of LH e. to increase sperm motility
Which of the following is TRUE of asexual reproduction?
a. It allows an individual’s genes to adjust to the environment. b. It produces greater genetic diversity. c. It is a good strategy if an organism lives in a constant, unchanging environment. d. It slows the accumulation of potentially harmful mutations. e. It allows only half of an individual’s genes to be passed on.