Which division of the nervous system consists of 12 pairs of cranial nerves?

the peripheral nervous systemperipheral nervous system (PNS).

What system consists of 12 pairs of cranial nerves?

The Sensory-Somatic Nervous System

The Sensory-Somatic Nervous System. The sensory-somatic system consists of 12 pairs of cranial nerves and 31 pairs of spinal nerves.

What division of the nervous system are cranial nerves?

peripheral nervous system

The cranial nerves are considered components of the peripheral nervous system (PNS), although on a structural level the olfactory, optic and terminal nerves are more accurately considered part of the central nervous system (CNS). The 12 pairs of cranial nerves are special nerves associated with the brain.

Are cranial nerves sympathetic or parasympathetic?

The nerve fibres of the parasympathetic nervous system are the cranial nerves, primarily the vagus nerve, and the lumbar spinal nerves. When stimulated, these nerves increase digestive secretions and reduce the heartbeat.

Are cranial nerves somatic or autonomic?

The peripheral nervous system is divided into the somatic nervous system and the autonomic nervous system. In the somatic nervous system, the cranial nerves are part of the PNS with the exception of the optic nerve (cranial nerve II), along with the retina.

Where are the 12 cranial nerves located?

The cranial nerves are a set of 12 paired nerves in the back of your brain. Cranial nerves send electrical signals between your brain, face, neck and torso.

What is made up of 12 pairs of cranial nerves and 31 pairs of spinal nerves?

The nervous system division that consists of 12 pairs of cranial nerves and 31 pairs of spinal nerves is the peripheral nervous system (PNS). The major divisions of the nervous system are the PNS and the CNS (central nervous system). The CNS is composed of the brain and the spinal cord.

What is the 12 cranial nerves and functions?

Overview of the 12 CNs

CN Function Quality
I—olfactory nerve (smell) Transmits signals from the olfactory organ (nose) to the brain Somatosensory and afferent
II—optic nerve (vision) Transmits visual signals from the retina to the brain Somatosensory and afferent

What are the 2 divisions of the nervous system?

The nervous system has two main parts: The central nervous system is made up of the brain and spinal cord. The peripheral nervous system is made up of nerves that branch off from the spinal cord and extend to all parts of the body.

How do you remember the 12 cranial nerves?

Youtube quote:Two the optic nerve followed by the oculomotor nerve cranial nerve for mr. Trochlea nerve then comes the trigeminal nerve abducens.

How many pairs of cranial nerves are mixed nerves?

4 pairs

4 pairs of cranial nerves are mixed nerves. These are trigeminal, facial, glossopharyngeal and vagus nerves.

What is sympathetic and parasympathetic?

The autonomic nervous system comprises two parts- the sympathetic and parasympathetic nervous system. The sympathetic nervous system activates the fight or flight response during a threat or perceived danger, and the parasympathetic nervous system restores the body to a state of calm.

What are neurones?

Neurons are information messengers. They use electrical impulses and chemical signals to transmit information between different areas of the brain, and between the brain and the rest of the nervous system.

What is a synapse Class 10?

Synapse is the gap between nerve ending of one neuron and dendrites of another. At synapse, the electrical impulse generated at dendrites of a neuron is passed on to dendrite of another neuron in the form of chemicals by on ending of the first neuron.

What are Ranvier’s nodes?

Nodes of Ranvier. These are the gaps formed between the myelin sheath where the axons are left uncovered. Because the myelin sheath is largely composed of an insulating fatty substance, the nodes of Ranvier allow the generation of a fast electrical impulse along the axon.

What are neurons Class 9?


A neuron consists of a cell body which comprises of nucleus and cytoplasm, from which long thin hair-like parts arise. The neuron has a single long part, called the axon, which transmit the nerve impulse to body parts. The neuron has short, branched parts called dendrites.

What is nerve cell Class 12?

Nerve cell- Nerve cells are also known as neurons. A neuron consists of 3 parts. (i) Cell body − It contains a nucleus and cytoplasm. (ii) Axon − It is a long part arising from the cell body. It transmits impulses away from the cell body.

What is neuron Class 11?

Hint: Neurons are the nervous system’s specialized cells that transmit signals throughout the body. Also, they are called nerve cells. Neurons have long branches that stretch out of the dendrites and axons called the cell body.

What is neuron and its function Class 10?

Neurons are the fundamental unit of the nervous system. Neurons are also called as nerve cells. The main function of the neurons is to pass the receiving information and send appropriate signals to the rest parts of the body. The signals received are in the form of electrical signals.

What is neuron Class 10 Ncert?

Neuron also known as a nerve cell is the functional and structural unit of the nervous system which has the capability to get excited by electrical or chemical impulse. These cells help in communication inside the body. These cells are found in animals except sponges whereas plants and fungi lack these cells.

What is a neuron Class 8?

Neurons are the building blocks of the nervous system. They receive and transmit signals to different parts of the body. This is carried out in both physical and electrical forms.

What is a neuron Class 7?

Neurons are the building blocks of the nervous system. It is defined as the specialized cells that help to transmit information to other parts of the body through electrical and chemical impulses. They are found in the brain, spinal cord, and peripheral nerves. It is also referred to as a nerve cell.

What is a reflex action class 10?

A reflex action is an automatic (involuntary) and quick reaction to a stimulus that protects the body from potentially dangerous situations like touching something hot.

What is reflex arc Class 11?

REFLEX ARC: Reflex arc is the nerve pathway involved in a reflex action, including at its simplest a sensory nerve and a motor nerve with a synapse between. Reflex arc consist of 1)Receptor or sensory organ, 2)Sensory neurine, 3)Reflex centre(brain or spinal cord), 4)Motor neurone and 5)Effector(muscle or gland). Q2.

What is reflex arc Class 9?

The reflex arc is the nerve pathway that is followed by reflex action. An example of the reflex arc is it happens when we accidentally touch something hot. The change in temperature is detected by the receptor first. Then electrical impulses are sent to relay neuron which is located in the spinal cord.