The Nervous System

The Nervous System By: Fazila Hussain Endi Sabanagic Amanda Martensen

Parts of the Brain • Brain stem- It connects the spinal cord to the forebrain and cerebrum. • Thalamus- It relays sensory impulses to the cerebral cortex. • Spinal Cord- it extends from the medulla oblongata through the spinal column and from which the spinal nerves branch off to various parts of the body. • Limbic System- in the brain it is involved in emotional behaviorCerebellum- It is responsible for the regulation and coordination of complex voluntary muscular movement as well as the maintenance of posture and balance. • Midbrain- It develops from the middle section of the embryonic brain • Medulla- It forms a medullary sheath around the axis cylinder of some nerve fibers.

Parts of the Nervous System • Brain • Spinal cord • Somatic Division • Automatic Division

Synapse • At a synapse, a slender terminal fiber from a neutron reaches out to make contact with another cell. If a nerve impulse flashes along the fiber, it makes the synapse release a chemical called a neurotransmitter. In less than one-thousandth of a second, this travels across a tiny gap between the two cells and triggers the second cell to respond.

Reflex • Reflexes are triggered by simple nervous pathways. A stimulus such as pain, is picked up by a sensory nerve and then flashed to the spinal cord, or to the lower part of the brain. A motor signal travels back, making part of the body respond.

One Problem/diseases of the Nervous System • Disease- intestinal disorders and headaches it happens when the nervous system is unwittngly trained to respond incorrectly to stress. • Treatment-Train people with certain disorder to get well. The mennger foundation, for example it’s still used to help migraine patients, but such programs remain the exception. • Prevention- Don’t take to much stress so that you get headaches.

One drug and its effect on the Nervous System • Cocaine it can cause a severe damage to the nervous system. It can also cause reduced fatigue, increased mental clarity, and a rush of energy.

Brain The portion of the vertebrate central nervous system that is enclosed within the cranium, continues with the spinal cord and composed of gray and white matter. The primary center for the regulation and controls of body activities, receiving and transmitting information to the muscles and body organs. The seat of consciousness through the memory, and emotion.

Spinal cord • The thick whitish cord of nerve tissue that extends from the medulla oblongata doen through the spinal column and from which the spinal nerves branch off.

Cerebellum • The trilobite structure of the brain, lying posterior of the pans and medulla oblongata and inferior to the occipital lobes of the cerebral hemisphere, that is responsible for the regulation and coordination of complex voluntary muscular movement as well as the maintains of posture and balance.

Cerebrum • The large round structure of the brain occupying most of the cranial cavity, divided into two cerebral hemisphere that are joined at the bottom by the corps callosum. Controls and integrates motor, sensory, and higher mental functions, such as though, reasons, emotion and memory.

Medulla Oblongata • The lower most portion of the vertebra brain, continues with the spinal cord, responsible for the control of respiration, circulation, and certain other bodily functions.

Hypothalamus • The part of the brain that lies below the thalamus. Forming the major portion of the ventral region of the diencephalons and functioning to regulate bodily temperature, certain metabolic process, and other autonomic activities.

Thalamus • A large ovoid of gray matter situated is the posterior part of the forebrain that relays sensory impulses to the cerebral cortex.

White matter • Whitish nerves tissue, especially of the brain and spinal cord, consisting of myelinated nerve fibers.

Gray matter • Brownish-gray nerve tissue, especially of the brain and spinal cord , composed of nerve cell bodies and their dent rites and some supportive tissues.

Central Nervous System • The portion of the vertebrate nervous system consisting of the brain and spinal cord.

Peripheral Nervous System • The part of the vertebrate nervous system consisting the nerves outside the central nervous system and including the cranial nerves, spinal nerves, and sympathetic and parasympathetic nervous system.

Somatic Nervous System • Part of the Peripheral Nervous System associated with the voluntary control of body movements through action of the skeletal muscles. Responsible for muscle contraction.

Autonomic Nervous System • The part of the vertebrate nervous system that regulates involuntary action, as of the intestines, heart, and glands, and that is divided into the sympathetic nervous system and the parasympathetic nervous system.

Neuron • Any of the impulse-conducting cells that constitute the brain, spinal column, and nerves, consisting of a nucleated cell body with one or more dendrites and a single axon. Also called nerve cell.

Sensory Neuron • A neuron conducting impulses inwards to the brain or spinal cord.

Motor Neuron • A neuron that conveys impulses from the central nervous system to a muscle gland, or the other effect or tissue.

Interneuron • A nerve cell found entirely within the central nervous system that acts as a link between sensory neurons and motor neurons.

Hypothalamus • The part of the brain that lies below the thalamus, forming the major portion of the ventral region of the diencephalon and functioning to regulate bodily temperature, certain metabolic processes, and other autonomic activities.

Axon • Also called a nerve fiber, this is the long tail of a neuron that carriers nerve impulses away from it’s cell bodys.

Dendrite • Short filament that carriers nerve impulses to the cell body of a neuron.

Nerve Impulse • Tiny electrical signal that passes along a neuron (nerve cell) at high speed.

Nerve • Cabelike bundle of neurons (nerve cell) that relays nerve impulses between the body and central nerve system.

Receptor • Special cells or neurons that detect stimuli such as light and trigger sensory neurons.

Synapse • Junction between two neurons in which they do not touch but come very close to each other.

The Nervous System