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.
Explanation:
1.Structure of virus- Schleiden and Schwann could not explain the structure and functioning of virus cell. They said that the function of body is coordinated function of cell which is not true in the case of virus because it only starts it's functioning when hosted by bacterial, plant or animal cell.
2.Prokaryotic cells- The cell theory do not holds true in the case of Pk cells because they do not have any well defined nucleus.
3.Multinucleate condition- The cell theory says that each cell have A NUCLEUS, but there are certain cells like tapetal cells that are coenocytic.
4.Cells without nucleus- Acc to cell theory there should be a nucleus in every cell, but human RBCs, sieve tubes of angiosperm are some of the cells lacking nucleus.
Answer:
The neuron will fire an action potential.
Explanation:
A neuron is a cell in the brain that transmit signals to other nerve cells.
The depolarization of a neuron occurs when the neuron moves to a cell membrane with a more positive value which makes it more likely to fire an action potential.
This could lead to the decrease in the areas sea star population. If there is not enough food, the animals may not be able to survive.
