As it binds to adenosine receptors, it slows down our nerve cell activity, which then causes drowsiness. A nerve cell mistakes caffeine for adenosine. Therefore, caffeine binds with the adenosine receptor, but rather than slowing down the cell's activity, the nerve cells speed up. While adenosine opens up blood vessels, allowing for more oxygen intake, caffeine constricts these blood vessels.
windshield - transparent screen (as of glass) to protect occupants of a vehicle. windscreen. aeroplane, airplane, plane - an aircraft that has a fixed wing and is powered by propellers or jets; the flight was delayed due to trouble with the airplane.
A windshield survey is conducted from a car and provides a visual overview of a community. Conditions and trends in the community that could affect the health of the population are noted. This data provides background and context for working in the community or for conducting a community assessment.