Going upward from the surface, it is the point where air ceases to cool with height, and becomes almost completely dry. More formally, the tropopause is the region of the atmosphere where the environmental lapse rate changes from positive, as it behaves in the troposphere, to the stratospheric negative one. Following is the exact definition used by the World Meteorological Organization:
The boundary between the troposphere and the stratosphere, where an abrupt change in lapse rate usually occurs. It is defined as the lowest level at which the lapse rate decreases to 2 °C/km or less, provided that the average lapse rate between this level and all higher levels within 2 km does not exceed 2 °C/km.<span>[1] for example</span>
Answer:
The tree main cell components are: plasma membrane, cytoplasm and nucleous
Explanation:
The plasma membrane is the a bilipid membranous layer composed of proteins and carbohydrates.
The cytoplasm is a jelly-like substance composed of mainly water and found between the cell membrane and nucleus.
The nucleous is an organelle which contains genetic information (DNA) on special strands called chromosomes.
Speed up chemical reactions (Catalysts)