Which of the following are the reasons why cells need to remain small? * To efficiently obtain nutrients
To efficiently remove waste products
To efficiently send signals to the center of the cell
All of the above

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

answer; i believe that the correct answer is (lung);

the answer is c on e2020, bud.