Nervous System Flashcards
The central nervous system serves as what? By? Which are designed to what?
The control center of the body by integrating mass communication networks consisting of billions of nerve cells called neurons, which are designed to convey information.
What are the three major functions of the nervous system? What are they also referred to as?
Sensory, integrative and motor functioning. The neural network.
What is the purpose of the neural network?
To gather information about our inner and external surroundings, process and interpret the information, and then respond to this stimuli. The messages are relayed back and forth between different parts of the body.
What is the sensory function?
Gathers information about inner and external surroundings.
What is the integrative function?
Processes and interprets the information from the sensory function.
What is the motor function?
Responds to the stimuli that is processed and interpreted from the integrative function.
In what order does the three major functions of the nervous system go?
1) Sensory
2) Integrative
3) Motor
The neuron is the ___.
Functional unit of the nervous system.
What happens when neurons merge?
They create the nerves of the body.
What does the structure of neurons allow for? (2 things.)
1) Allows for very quick communication to and from the cell
2) As well as continuous conduction of signals across the neuron.
What is a neuron’s main component? Which contains what?
A cell body, or soma, which contains the organelles important to the proper functioning of this cell.
What is the long branch that projects out of the soma called? And what does it do?
It’s called the axon and it feeds information through nerve impulses to muscles, organs, and other neurons.
What are the shorter branches that project from the soma called? What do they do?
They’re called dendrites and they bring information from other neurons of the nervous system.
All the communication occurs across junctions referred to as ________, which occur either between ________________.
synapses.
neurons or between a neuron and another cell type.
What is a synapse?
A tiny empty space between two axons or dendrites from different cells.
What happens within synapses?
What does this stimulate?
This is how the continuation signal the neuron was transmitting makes it to the ____ ?
For example, a signal to move your finger would _____________.
Neurotransmitters are released from the neurons before the synapse and bind to the receiving cells located after the synapse.
This stimulates a signal that is called an action potential, which travels to the receiving cell, called a receptor, and the on to the cells that act on the signal in the desired location.
This is how the continuation signal the neuron was transmitting makes it to the end location.
For example, a signal to move your finger would travel from the brain, through many neurons and finally to the muscle in the finger.
What are neurotransmitters?
They are the major chemical messengers of the nervous system.
What are receptors?
Receiving cells.
What are neurons usually covered in? And therefore are said to be?
A layer of insulation called myelin and therefore are said to be myelinated or covered in a myelin sheath.
What does myelin insulation help do?
Helps signals to be transmitted faster from one nerve cell to another.
Where are many nerve cells not myelinated and why?
The brain because they are located close together.
Nerve cells that have long axons or dendrites need what?
Myelin to speed up the transmission time for their signals.
What are the three different kind of neurons?
Interneurons, motor neurons and sensory neurons.
What do interneurons do?
Transmit signals from one neuron to another neuron.
What do motor neurons do?
Send signals from the spinal cord or the brain to other areas of the body.
What do sensory neurons do?
Send signals from areas of the body to either the spinal cord or to the brain.
The nervous system is composed of two major compartments. What are they?
The central nervous system (CNS) and the peripheral nervous system (PNS).
What does CNS and PNS stand for?
Central Nervous System and Peripheral Nervous System.
What two “parts” are collectively known as the CNS?
The brain and the spinal cord.
How would you describe a spinal cord?
As a long continuation of the brain.
What is the source of conscious and unconscious thoughts, moods and emotions?
The central nervous system.
What is the Peripheral Nervous System comprised of?
All the nerves in the body, including the cranial and spinal nerves.
What are the four sections of the brain?
1) Cerebrum
2) Diencephalons
3) Cerebellum
4) Brain stem
What is the largest part of the brain?
The cerebrum, which makes up 85% of the brain’s total weight.
The cerebrum is divided into what? And what do they do?
Left and right hemispheres and they communicate with each other to control muscles and organs as well as thought, hearing and language.
What is the outer portion of the cerebrum called? Which is primarily what?
The cerebral cortex, which is primarily gray matter containing nerve cells.
The central part of the brain is called the what? And what does it include?
The diencephalon, which includes glands important of the release or regulation of hormones.
Where is the cerebellum located? What is its function?
At the rear of the brain. Controls balance, posture and coordination.
What does the brain stem connect? And what is it the center for?
Connects the cerebrum and cerebellum.
It is the center for the control of visual and auditory reflexes, heart rate, blood pressure and breathing.
The entire brain is protected by what? Where are they located?
Three layers of membranes called meninges, which are located just under the skull.
Where does the spinal cord branch out from? And what is its function?
Branches out from the brain stem.
To send, receive and interpret nerve signals traveling between the brain and the rest of the body.
What is the Peripheral Nervous System divided into?
The voluntary nervous system (somatic) and the involuntary nervous system (autonomic).
Another name for the voluntary nervous system?
Somatic.
Another name for the involuntary nervous system?
Autonomic.
What does the somatic system do?
Signals skeletal muscles to control voluntary movement.
What does the autonomic system do?
Regulates the contraction of internal organs and there controls involuntary physiological processes like heart rate, digestion and breathing.
Since the autonomic system can accelerate or decelerate its processes and functions, what are the two distinct pathways of the autonomic nervous system (ANS)?
The sympathetic pathways and parasympathetic pathways.
What does ANS stand for? What is it comprised of?
The autonomic nervous system. The sympathetic pathways and the parasympathetic pathways.
What does the sympathetic pathway of the ANS do?
Kicks in under stress conditions and responds accordingly, usually accelerating bodily functions like heart rate.
What does the parasympathetic pathway of the ANS do?
Usually slows down bodily functions in rest conditions.
When beginning an exercise program, why is it important that nervous system be properly trained?
To ensure that the right movement patterns are being developed.
All movement within the body is directly associated with the ________.
Nervous system.
What are two benefits of training the nervous system when beginning an exercise program?
Improve performance and decrease the risk of injuries.
What are mechanoreceptors?
They are the primary neurons important to fitness and physical movement, and they respond to mechanical forces.
Where are mechanoreceptors found? And what do they do?
They are found in muscles, tendons and ligaments and are responsible for sensing distortion in tissues, such as induced by exercise.
