The endoplasmic reticulum can either be smooth or rough, and in general its function is to produce proteins for the rest of the cell to function. The rough endoplasmic reticulum has on it ribosomes, which are small, round organelles whose function it is to make those proteins.
I believe that it's an exhausted bear. Cellular respiration is the way plants and animals receive energy. If the bear is exhausted, it means it's cellular respiration is lacking.
The nervous system, i could be wrong.
Answer:
A) they help transport some substances through the membrane.
Explanation:
The membrane proteins that span the bilayer of phospholipids help in the transport of polar, large and charged substances across the membrane. The nonpolar core of the membrane does not allow these charged and polar substances to pass through. Proteins serving as channels form pores to allow movement of the specific substances.
On the other hand, carrier transport proteins of the membrane bind to the substances present at one side of the membrane and deliver them to the opposite side.
The answer is 90 and 140 mm Hg.