They allow passage for large molecules which cant normaly diffuse throught the phopholipid layer and import and export ions
<em>Answer:</em>
<em>A group of cells working together is defined as a tissue and several tissues working together comprise an organ. ... The heart is used as an example of an organ which is made up from muscle and valve tissue.</em>
<em>Explanation:</em>
Because if they run out they will take a long time to remake themselves
<span>What happens to them would basically happen to everything only the earth's surface is more robust. The answer is c. they fold to create ridges and valleys perpendicular to the direction to which pressure is applied. This means that it takes the form based on the force that is applied to it which is in this case horizontal, meaning from sides instead of vertical which would be from up or down.</span>
The ozone layer over the Arctic change with the seasons as "it peaks in spring and decreases in fall".
<u>Option: B</u>
<u>Explanation:</u>
The variations with the seasons in ozone layer over the Arctic is triggered by Polar Stratospheric Clouds (PSCs) developing in the polar regions during winter. These clouds have a surface area where the chemical reaction of CFC occurs at a rapid rate that induces ozone depletion in the polar stratosphere by as much as 50%. It occurs in the spring, as the temperature begins to warm up, resulting in an rise in the chemical reaction rate of these cloud surfaces.