Exercise Science: Nervous System

Objective

Students will be able to differentiate between the central and peripheral nervous systems. They will also be able to describe the role the nervous system plays in creating bodily movement. ​

Subject | Subject

Some text here about the topic of discussion

What is the Nervous System?

• communication and command system of the body

• Senses changes in and around the body

• Responds to these changes with some form of muscle contraction or gland secretion. ​

• Nerves can either be excitatory or inhibitory.​

Some text here about the topic of discussion

• ​ Consists of nerves extending from the brain and spinal cord.

• Acts as the bridge for information between one's environment and the CNS.

PNS

• Includes the brain and spinal cord

• Take in info, process info, and send out motor signals

• Body's main "Control Center"

CNS

Some text here about the topic of discussion

• ​Efferent neurons send output from the CNS to the glands and muscles.

• Efferent neurons​ can be divided into the somatic and autonomic nervous systems

Efferent Neurons

• ​The skin, joints, tendons, muscles, internal organs, and sense organs send sensory information to the CNS using Afferent neurons

Afferent Neurons

Some text here about the topic of discussion

• ​Excites involuntary organ muscles

• Stomach, intestines, blood vessels, and heart. ​

​

Autonomic Nervous System

• ​Consists of motor neurons

• Stimulates skeletal muscle

• Voluntary​

​

Somatic Nervous System

Some text here about the topic of discussion

• ​ Dendrites: Translates sensory messages to the cell body from other neurons.

  • ​ex. temperature, pressure, touch, etc

• ​ Cell body: contains the nucleus

• ​ Axon: transmits messages from the cell body to its end organs.

• Synapse: the junction between two nerves.​

​

​

​Some text here about the topic of discussion.

Structure of a neuron

​

​ We basically all have super powers! Your body can actually take information from the world around us, turn that into an electrical charge that gets sent throughout our bodies and causes some kind of action.

Fun Fact:

​

​​1.Resting potential: -70 millivolts

2.Depolarization: Cell membranes charge becomes less negative (via NA+, K+ pump)

3.Threshold: -50 to -55 millivolts​ (all or none)

4.Action potential occurs

5. Repolarization: neuron restores itsself to resting membrane charge (-70 millivolts)​

​

• ​ While nerves communicate from nerve to nerve through synapses, Nerves communicate with muscle fibers through neuromuscular junctions.

• The function of the neuromuscular junction is​ to transmit the electrical impulse from the nerve to the muscle

​

​

​Some text here about the topic of discussion.

Neuromuscular ​Junction

​

Proprioceptors​

• ​ Specialized receptors in muscles, joints, and tendons.

• Relay messages to the CNS about muscular changes in the body and about limb movement. ​

• For example, proprioceptors help subconsciously maintain posture and balance when performing a lunge, or inhibit the stretch should the lunge be too deep.

Subject | Subject

Some text here about the topic of discussion

Stretch Reflex

• ​This is a response of the central nervous system to inhibit the stretch in a muscle or cause it to contract.

• ​ This protects the muscle from extreme ranges of stretch or from stretches that are performed too fast.

Subject | Subject

Some text here about the topic of discussion

Golgi Tendon Organs

• ​ Lie within the tendons and recognize changes in tension in the muscle.

• In response to muscle tension, the CNS may reflexively send a message to suppress the muscular force.

• For example, If you lift a barbell that is too heavy for you, the Golgi tendon organs elicit an inhibiting message that goes to the muscle, not allowing further movement and thus protecting the muscle from damage.​

Subject | Subject

Some text here about the topic of discussion