Many enzymes consist of a protein and a non-protein (called the cofactor). The proteins in enzymes are usually globular. The intra- and intermolecular bonds that hold proteins in their secondary and tertiary structures are disrupted by changes in temperature and pH. This affects shapes and so the catalytic activity of an enzyme is pH and temperature sensitive.
Everyday in the U.S. millions of cars and trucks idle needlessly, sometimes for hours. You may not be able to avoid keeping your engine running when youâre stopped at a traffic signal or stuck in slow-moving traffic. But other times idling is unnecessary. An idling car can release as much pollution as a moving car.
Q: How long/far does one have to drive a car to recharge a dead battery after receiving a jump-start? â Marvin Goldstein, Blue Bell, Pa. A: The general rule is you should drive the car for 15 to 30 minutes after a jump-start to make sure the battery gets a decent charge.However, if the battery was close to being completely discharged, it will need to be hooked up to a charger to top it off. Marvin Goldstein, Blue Bell, Pa. A: The general rule is you should drive the car for 15 to 30 minutes after a jump-start to make sure the battery gets a decent charge.