True or False: all cells have a cell membrane.

A True
B False​

True

Explanation:

all cells have plasma membrane ( cell membrane ) the plasma membrane, or cell membrane, is the phospholipid layer that surrounds the cell and protected from outside

 True.

Explanation:

All cells in the world have a outer plasma membrane that regulates not just what enters the cell, but also how much of any given substance comes in the cell. But unlike prokaryotes, eukaryotic cells also have membranes on the inside of them that protect their organelles and also control the exchange of important cell parts.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.