Plants: haploid generation of a plant produces gametes (sperm and eggs) and is called the gametophyte; the diploid generation produces spores and is called the sporophyte/ diploid zygote.
1 You gain the most benefits and lessen the risks when you exercise in your target heart rate zone. 2  Usually this is when your exercise heart rate (pulse) is 60 to 80 percent of your maximum heart rate. 3  In some cases, your health care provider may decrease your target heart rate zone to begin with 50 percent.
Target Heart Rate Your heart rate is one of the easiest measurements to take to determine your level of exertion during exercise. The American Heart Association recommends working in a safe target heart-rate zone between 50 and 85 percent of your maximum heart rate. An 18-year-old boy can find his maximum heart rate by subtracting his age from 220. This would put his maximum heart rate at 202 beats per minute, meaning he should exercise between 101 and 172 beats per minute. An 18-year-old girl can subtract 88 percent of her age from 206, putting her maximum heart rate at 190 beats per minute and her target heart-rate zone between 95 and 162 beats per minute.