Villi are finger-like projections richly supplied with . They help in in the small intestine.

Why do you think the puppy litter was all dark-haired?

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

8) animals respond in various ways to stimuli detected through their senses. some of these responses are stimulated by the presence of danger. which of these animal responses is the best example of a response to an immediate threat? a) a rooster crows every morning at the first sign of light. b) as something approaches an octopus, it shoots a cloud of ink. c) from late fall until spring, bears hibernate to preserve energy. d) a dog is getting hot in the sunlight, so he moves to a shaded area.