D. Have Different Structures and Different Functions
<span>The proteins that are embedded in the cell membrane act as channels to transport substances in and out of the cell.</span>
Answer:
d. The normal pH of human blood is already in the alkaline range.
Explanation:
The blood has an average pH between 7.35 and 7.45. Also, in blood there are some natural buffers that allows to maintain this pH does not matter the kind of food or substances that enter to our body.
If for any process the pH decreases a little bit, the body starts a process to recover the natural pH of the blood.
One example: The improvement in science and technology over the years has decreased the infant mortality rate. Since more babies live, we have a higher population.
Also, with increases in science and technology, there are many diseases that were once considered fatal that are now easily treated. This has also led to a higher population.
Answer:Sclerenchyma
Explanation:Sclerenchyma is thick walled dead lignified cells, they are hard and elastic. The sclerenchyma cells are divided into two groups namely fibers and sclereids. Sclerenchymatous fibers are branched/unbranched, long, hard, pointed cells with tapering ends, thick walls, and narrow lumen.