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.
Most windshields are made up of one of three colors: Blue, Green or Clear. If you look at your windshield (unless itâs a Jeep Wrangler) you will see that it is tinted slightly. If you look at the top six inches or so, you will probably see a darker strip of tint. That is to block the direct sun rays. Sometimes this tint can be bronze, green or blue. This is a blue windshield with blue tint.