2. Bella wants to know which mode of transportation is the fastest for getting from her home to the grocery store. She can drive her car, ride her bike, walk, or charter a helicopter.

In which of the following ways is the function of the surface of a microsphere similar to the function of an actual cell membrane? a. both make it possible for the conditions in the interior to be different from the conditions outside. b. both provide a barrier that keeps water from flowing across it so the interior remains dry. c. both separate the rna that forms in the interior from any rna that might form in the environment. d. both can actively move molecules into the interior or out into the surrounding environment.

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

Blood stem cells may develop into any kind of human blood cells. what kind of stem cells are blood stem cells? a. multipotent stem cells o b. totipotent stem cells o c. pluripotent stem cells o d. unipotent stem cells