Question
Question: Which cranial nerves have the highest number of branches? A. Trigeminal nerve B. Facial nerve ...
Which cranial nerves have the highest number of branches?
A. Trigeminal nerve
B. Facial nerve
C. Vagus nerve
D. None of the above
Solution
Vagus is the longest nerve which is spread all around the body. Trigeminal and facial nerve is a local nerve.
Complete answer:
Trigeminal nerve is the local nerve responsible for sensation in the face, helping in chewing and biting of food and act as the most complex nerve. It has only main branches. Hence due to its complexity, it is categorized into 3 branches only. So, it is incorrect.
Facial nerve is mainly responsible for controlling muscles of facial expression as well as taste sensation. It has only 5 major branches. So, it is the local nerve and hence present only at a specific location. Hence, it cannot be the highest.
Vagus nerve has the highest number of branches. It originated from medulla oblongata of brainstem. Vagus nerve is also called pneumogastric nerve. It is the tenth cranial nerve. It is involved in parasympathetic control of heart, lungs and digestive tract. In autonomic nervous systems, it is the longest.It is composed of sensory and motor fibres.It passes through the jugular foramen, then through the internal jugular vein to neck, chest and abdomen. Vagus nerve conveys sensory information from different body organs to the central nervous system.
Vagus nerve is branched at the neck region. Majorly it is the right vagus nerve and left vagus nerve. The right vagus nerve is passed by anterior to the subclavian artery and posterior to the sternoclavicular joint. The left vagus nerve is passed between the left common carotid and left subclavian arteries, posterior to the sternoclavicular joint. The several other branches are named as follows: pharyngeal nerves, superior laryngeal nerves, recurrent laryngeal nerve and superior cardiac nerves. The major functions of the vagus nerve are communication between brain and gut, lowering of heart rate, breathing rate, blood pressure, stress, anxiety etc.
So, option C is the correct answer.
Note:
Extensive range of signals are carried out by the vagus nerve. It is one of the most important nerves of the human body.