A renewable resource is something that provides power but will never run out. Eventually natural gas and oil and coal will run out. Wind is renewable because it will never run out, unless the world ends, then it won't matter.
Answer:
The hydrophilic part of the cell membrane is A, the phosphate head.
Charged molecules, such as K+ or Ca++ are unable to pass through the lipid bilayer because of their charge and must use a membrane protein to cross the cell membrane.
C, the lipid tails, are hydrophobic and repel water.
<u><em>-Why does the lysosome have a different pH than the cytoplasm? </em></u>
The pH within lyosomes is more acidic than the pH of the cytoplasm because Enzymes within the lysosomes aid the breakdown of proteins, polysaccharides, lipids, nucleic acids, etc. These enzymes are active at a much lower pH than that of the cytoplasm. Thus the different pH from the cytoplasm.
<u><em>-What is the advantage of having several smaller chloroplasts and not just 1 huge one?</em></u>
The advantage of having several smaller chloroplasts and not just 1 huge one increases the surface area for the light to be absorbed. As a result, more light energy can be utilized.
The sarcoplasmic reticulum helps to trigger muscle cell contraction by releasing Calcium into the cytoplasm
Plasma Membrane is the answer
