(b)Decreases
The growing season often lasts all year in equatorial and tropical locations, but it can be as short as two months or less in higher latitudes, such as the tundra. Grwoing season varies depending upon the temperature ranges, most plants favour growing in ranges of 18-28 degree celcius, since the temperature is normallly higher at equator, the life cycle is prolonged, whereas in non-equatorial regions, it is shortenend.