Frog Nervous System Short Notes | Free Biology Notes

In this article we will discuss about the frog nervous system

Frog Nervous System

• The set of organs which control and coordinate all the activities of the body is called the nervous system
• The frog nervous system composed of CNS, PNS and ANS

Central nervous system

• CNS is made up of brain & spinal cord
• CNS controls most functions of the body

Brain

• The brain is protected in the brain case or cranium
• It is surrounded by two meninges
• Inner cavities of brain are filled with cerebrospinal fluid
• Cerebrospinal fluid is a clear, watery and lymphatic fluid. It protects and nourishes the brain
• Brain has three parts which are called fore brain, mid brain and hind brain

Fore Brain

• The most anterior region comprises the olfactory lobes
• Olfactory lobes are concerned with sense of smell
• Immediately behind the olfactory lobes, there are two large outgrowths called the cerebral hemispheres
• Hemispheres are place of memory, intelligence, consciousness

Midbrain

• Posterior to the cerebral hemispheres are called optic lobes
• The part between the optic lobes and hemispheres is known as the diencephalon
• This part is associated with the eyes and vision.

Hind Brain

• The last part of the brain consists of the cerebellum and the medulla oblongata.
• This part controls and coordinates body movements and maintains balance of the body
• The medulla oblongata also controls respiration. circulation and digestion

Spinal Cord

• The spinal cord starts from the posterior end of the medulla oblongata like a thick thread
• Spinal cord are not solid, which is filled with a fluid
• The spinal cord controls the movement of the trunk area and many other functions independently

Peripheral nervous system

• Peripheral nervous system consists of nerves, which connect the central nervous system with various parts of the body
• They are of two types:
  1. Cranial nervous: nerves originating from brain are called cranial nerves. In frog. There are ten pairs of cranial nerves.
  2. Spinal nerves: nerves originating from spinal cord are called spinal nerves. There are nine or ten pairs of spinal nerves.
• Nerves are of following types:
  • Sensory nerves: these nerves take messages from sensory organs to central nervous system.
  • Motor nerves: these nerves take messages from central nervous system to glands and muscles.
  • Mixed nerves: they carry out both the above mentioned functions.

Autonomous nervous system

• This controls the autonomous parts (automatic) of the body
• This system control the autonomic parts of the body like heart, lungs & intestine
• Two type of nerves are present in it.
• Sympathetic nerve : it increase the rate of autonomous organs.
• Parasympathetic nerve : it decrease the rate of autonomous organs.