**20 points! ! ** which of the following might be connected to "temperature climates"? a. solar energy hits these regions at a low angle. b. year-round tempatures are always hot. c. weather generally changes with the seasons-hot in summer, cold in winter, and mild in spring and fall.

c. Weather generally changes with the seasons-hot in summer, cold in winter, and mild in spring and fall.

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation: