<span>Nitrogen and phosphorous are the most prevalent aquatic pollution and contribute heavily to the excessive growth of algae in aquatic environments called algae blooms. The nitrogen from the fertilizers is found in molecules called nitrates which are compounds of both oxygen and nitrogen. Phosphorous helps algae to absorb carbon dioxide. So when the phosphorous levels are high the algae absorbs more carbon dioxide, which allows for faster photosynthesis and faster glucose production which leads to faster growth. Although algae need both nitrogen and phosphorous to grow, when the levels are too high the algae grows faster than the ecosystem can sustain leading to oxygen deprivation for the other aquatic organisms.</span>
Well, usually the qn would be what is different between a compound and a molecule. but if you ask like this then, here goes.
An element is the simplest substance that can not be broken down into its components using physical processes. exp: Na, S, K
A molecule is a substance that make up of an element bonded together.
exp: O2, S2, F2(diatomic molecules)
Answer:
The answer is the accessory nerve.
Explanation:
We have 12 pairs of cranial nerves, the accessory nerve is the XI pair. This is responsible for the innervation of the sternocleidomastoid and trapezius muscles.
The fibers of the accessory nerve originate from neurons that are located in the upper spinal cord. These fibers join together forming roots and once the nerve is constituted, it enters the skull through the great hole that is located at the base of the skull.
Then, the nerve continues its path along the inside of the skull in the direction of the jugular hole and then leaves the skull next to the glossopharyngeal nerve (IX) and the vagus (X).
Thus, the accessory nerve enters and leaves the skull again, characterized by being the only cranial nerve which has this behavior.