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.
Windshield bags are functional accessories that provide valuable storage space. The large windshield bag is large enough to hold a garage door opener, cell phone and other small items. The large windshield bag will not work with bikes that have the factory tac.