In boys, the penis and scrotum begin to grow at an accelerated rate around age and reach adult size in years.

Which best describes an adaptation that could be found in a fish that lives in a slow-flowing stream? the ability to attract prey by glowingextra gills, for oxygen extractionthe ability to grow largerextra fat, for warmth

How can scientists test their ideas about the origin of the universe if they can't physically interact with or study?

All but one describes an effect of aging on the digestive system. a) decreased acid secretion b) decreased elasticity of stomach c) capacity to resist damage decreases d) food remains in stomach for less time