Nervous System
Major Functions
Central nervous system- The complex of nerve tissues that controls the activities of the body. In vertebrates it comprises the brain and spinal cord. Controls most functions of the body and mind. The brain is the center of our thoughts, the interpreter of our external environment, and the origin of control over body movement.
Peripheral nervous system- The nervous system outside the brain and spinal cord. The main function of the Peripheral Nervous System is to connect the central nervous system to the limbs and organs, essentially serving as a communication relay going back and forth between the brain and the extremities.
Brain - The cerebrum or cortex is the largest part of the human brain, associated with higher brain function such as thought and action.
Spinal cord - carries out two main functions: It connects a large part of the peripheral nervous system to the brain. Information (nerve impulses) reaching the spinal cord through sensory neurons are transmitted up into the brain.
Nerves - transmit signals between different parts of the body.
Neurons - Neurons are able to respond to stimuli (such as touch, sound, light, and so on), conduct impulses, and communicate with each other (and with other types of cells like muscle cells).
Peripheral nervous system- The nervous system outside the brain and spinal cord. The main function of the Peripheral Nervous System is to connect the central nervous system to the limbs and organs, essentially serving as a communication relay going back and forth between the brain and the extremities.
Brain - The cerebrum or cortex is the largest part of the human brain, associated with higher brain function such as thought and action.
Spinal cord - carries out two main functions: It connects a large part of the peripheral nervous system to the brain. Information (nerve impulses) reaching the spinal cord through sensory neurons are transmitted up into the brain.
Nerves - transmit signals between different parts of the body.
Neurons - Neurons are able to respond to stimuli (such as touch, sound, light, and so on), conduct impulses, and communicate with each other (and with other types of cells like muscle cells).
Path of a nerve impulse-
Receptors transform stimuli into electrical nerve impulses.
Sensory neurons relay the nerve impulse to the central nervous system
Relay neurons (also called inter neurons or connector neurons) transmit nerve impulses within the Central Nervous System.
Motor neurons receive nerve impulses from the Central Nervous System and relays the signal to an effector.
Effectors produce a response to the stimulus.
Synapses are the junctions between two nerve cells and the transmission of a signal across these junctions require chemical neurotransmitters.
Signals travel along the nerve through a depolarization wave called an action potential.
Frontal Lobe- associated with reasoning, planning, parts of speech, movement, emotions, and problem solving
Parietal Lobe- associated with planning of movement, orientation, recognition, perception of stimuli, and language
Occipital Lobe- associated with visual processing
Temporal Lobe- associated with perception and recognition of auditory stimuli, memory, and speech
Receptors transform stimuli into electrical nerve impulses.
Sensory neurons relay the nerve impulse to the central nervous system
Relay neurons (also called inter neurons or connector neurons) transmit nerve impulses within the Central Nervous System.
Motor neurons receive nerve impulses from the Central Nervous System and relays the signal to an effector.
Effectors produce a response to the stimulus.
Synapses are the junctions between two nerve cells and the transmission of a signal across these junctions require chemical neurotransmitters.
Signals travel along the nerve through a depolarization wave called an action potential.
Frontal Lobe- associated with reasoning, planning, parts of speech, movement, emotions, and problem solving
Parietal Lobe- associated with planning of movement, orientation, recognition, perception of stimuli, and language
Occipital Lobe- associated with visual processing
Temporal Lobe- associated with perception and recognition of auditory stimuli, memory, and speech
Two Sub Systems
Sympathetic nervous system - the sympathetic nervous system can accelerate heart rate; cause piloerection (goose bumps) and perspiration (sweating); and raise blood pressure. This is done as a response to stimuli in a balance with the parasympathetic nervous system. pupils dilating
parasympathetic nervous system - lowering blood pressure, slowing heart rate. pupils constricting
How it works with other systems
Nervous System
- Bones provide calcium that is essential for the proper functioning of the nervous system.
- The skull protects the brain from injury.
- The vertebrae protect the spinal cord from injury.
- Sensory receptors in joints between bones send signals about body position to the brain.
- The brain regulates the position of bones by controlling muscles.
- Endothelial cells maintain the blood barrier.
- Baroreceptors send information to the brain about blood pressure.
- Cerebrospinal fluid drains into the venous blood supply.
- The brain regulates heart rate and blood pressure.
Diseases
Alzheimer’s Disease - progressive mental deterioration that can occur in middle or old age, due to generalized degeneration of the brain. It is the most common cause of premature senility.
Parkinson’s Disease - a progressive disease of the nervous system marked by tremor, muscular stiffness, and slow, imprecise movement, mainly affecting middle-aged and elderly people. It is associated with degeneration of the basal ganglia of the brain and a deficiency of the neurotransmitter dopamine.
Parkinson’s Disease - a progressive disease of the nervous system marked by tremor, muscular stiffness, and slow, imprecise movement, mainly affecting middle-aged and elderly people. It is associated with degeneration of the basal ganglia of the brain and a deficiency of the neurotransmitter dopamine.