The Central Nervous System The central nervous system(CNS) is made of the brain and the spinal cord. It is protected by 2 sets of bones. skull – protects the brain vertebral column- protects the spinal cord
The Brain The brain is located at the anterior end of the spinal cord. The spaces between the brain are called ventricles.
The Brain The brain is made up of two main parts: forebrain brainstem
The Forebrain The forebrain subdivides to form : telencephalon cerebrum diencephalon thalamus hypothalamus
Hypothalamus and Thalamus thalamus hypothalamus •The hypothalamus is the bridge between the nervous messages before•The function of the thalamus is to sort and interpret theseand endocrine relaying themto the appropriate neurons in the cerebrum. regulates the pituitary gland. systems. It produces various hormones and
The Brainstem The brainstem functions below the level of consciousness , thus it is called the unconscious brain. The brainstem is the region of the brain that connects the cerebrum with the spinal cord. It is consists of : midbrain medulla oblongata pons
The Spinal Cord • • It contains a tiny ,centralcord descends down the middle From the brain the spinal canal filled withof the back and is is a long, thin, tubular bundle thenervous The spinal cord surrounded and protected by of bony cerebrospinal fluid. tissue and support cells that extends from the brain. vertebral column.
Peripheral Nervous System Somatic Nervous System - controls skeletal muscle as well as external sensory organs. Autonomic Nervous System - controls involuntary muscles, such as smooth and cardiac muscle.
Cells of the Nervous System 2 Kinds of Cells Neurons Glial Cells Neurons are specialized cells for the transmission of messages from an organ or tissue to another.
Glial Cells Glial cells, sometimes called neuroglia or simply glia provide support and protection for neurons. They are thus known as the "supporting cells" of the nervous system. Functions of glial cells are: to surround neurons and hold them in place to supply nutrients and oxygen to neurons, to insulate one neuron from another, and to destroy and remove the carcasses of dead neurons (clean up).
How the Nervous System Works Stimulus- any factor that triggers a specific reaction. Sensory neuron- is the neuron that receives the stimulus. Motor neuron- the neuron that relays the information to the part of the body for a response.
Sense organs carrymessages about theenvironment to the central nervous system.
The eyes, ears, nose, tongue, and skin are examples of sense organs The sense organs gather information (light, sound, heat, and pressure) from the environment
The eye is one of your sense organs.• The eye is made of the iris and the pupil.•The eye gathers pictures and sends them to thebrain. The colored part of the eye is the iris. The black part of the eye is the pupil. Iris Pupil The pupil becomes larger and smaller as it controls the light coming into the eye.
The ear is the organ of hearing and balance. Hearing starts when some of the sound waves go into the ear.
The ear works with the brain to control your balance. The liquid in your inner ear is responsible for your balance The liquid in your ear moves when we move. The liquid movement sends information to the brain to tell it how we are moving. Loss of sight can be one of the factors that affect the sense of balance.
Nose is the organ of smell. The nose has two holes called nostrils. The nostrils and the nasal passages are separated by a wall called the septum. Closer to the tip of your nose, the septum is made of cartilage.
Behind your nose, in the middle of your face, is a space called the nasal cavity. It connects with the back of the throat. The nasal cavity is separated from the inside of your mouth by the palate (roof of your mouth).
The tongue is the sense organ of taste controlled by the receptors called taste buds. The four kinds of taste sensations are sweet, sour, bitter, and salty. The tongue can also detect a sensation called umami. Umami is a Japanese word which means the savory taste of amino acids.
The sense of touch is located in the skin. The nerves in the skin allow us to feel texture, pressure, heat, cold, and pain.
Thank You For Watching & ListeningRemember : The nervous system is a complex network of nerves and cells that carry messages to and from the brain and spinal cord to various parts of the body. The nervous system includes both the Central nervous system and Peripheral nervous system. The Central nervous system is made up of the brain and spinal cord . The Peripheral nervous system is made up of the Somatic and the Autonomic nervous systems.