You are a molecule of water. Choose a starting point in the water cycle and describe the process you would go through to move through the entire cycle.

First the water which is present in the sea and ocean evaporated due to the radiation of sunlight which changes liquid into vapours. These vapours goes to the atmosphere and forms cloud. These clouds moves to the hilly areas by winds and falls in the form of rainfall and snowfall. The water which is present in these hilly areas starts melting due to increase in temperature and this water flows down the land through streams and again meets the ocean.

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: