Why do decreased testosterone levels in men lead to infertility?
a. lower testosterone prevents sperm from being made
b. lower testosterone prevents sperm from maturing
c. lower testosterone inhibits sperm motility
d. lower testosterone prevents ejaculation
e. lower testosterone prevents the removal of the coating on the head of the sperm
ANSWER: b
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What will be an ideal response?
In the 1600s, a Dutch scientist Anton van Leeuwenhoek made his own glass lenses for observing microorganisms. His observations were the first detailed look at the world of tiny living things. His lenses were rather simple devices however, and very different from the microscopes used in science classes today. The illustration below shows one of van Leeuwenhoek's devices.How do you think van Leeuwenhoek's devices were different from modern-day microscopes?
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