For example, a certain maize variety grown in a cool climate will need less water per day than the same maize variety grown in a hotter climate. It is therefore useful to take a certain standard crop or reference crop and determine how much water this crop needs per day in the various climatic regions.
An implantable cardioverter defibrillator (ICD) looks very similar to a pacemaker, except that it is slightly larger. It has a generator, one or more leads, and an electrode for each lead. These components work very much like a pacemaker.
A Pacemaker is less intrusive and your heart recovers more quickly, you also don't have to wait for a donor.No need for major surgery if you get a pacemaker.Disadvantage is that the operation may go wrong and pacemakers only last for a while, run on battery power.