Chapter 2 - Nervous System

Question 0

Nervous System

Answer 0

Main organ system

Control center for movement production

Responsible for the recruitment of muscles, learned patterns of movements, and functioning of every organ in the body.

Billions of cells designed to provide a communication network within body.

Divided into: CNS & PNS

Question 1

Human Movement System (HMS)

Answer 1

AKA Kinetic Chain

• Nervous, Skeletal & Muscular Systems
• Nerves, muscles & joints work together to produce motion.

Question 2

Central Nervous System (CNS)

Answer 2

ONLY brain & spinal cord

Question 3

Peripheral Nervous System (PNS)

Answer 3

Contains ONLY NERVES and connects the brain & spinal cord TO the REST of the body.

How CNS receives sensory input and initiates a response.
• activates different effector sites
• relay information from effector sites to brain - constant update to relation of body to environment.

2 parts:
• Somatic
• Autonomic

Question 4

Primary Functions of Nervous System

Answer 4

• Sensory function
• Integrative function
• Motor function

Question 5

Sensory function

Answer 5

Ability of the nervous system to sense changes in either the internal or external enviorment.

Ex: stretch placed on muscle (internal)
Or change from walking on pavement to side walk. (external)

Question 6

Integrative function

Answer 6

Ability of nervous system to analyze and interpret sensory information to allow for proper decision making, producing an appropriate response.

Question 7

Motor function

Answer 7

Neuromuscular (nervous and muscular system) response to sensory information.
Causing muscle contraction when stretched too far.

Ex: Changing movement pattern when waking in sand vs. on side walk

Question 8

Training Proprioceptively:

Answer 8

Improves balance, coordination, posture, and body’s ability to adapt to it’s surroundings.

Question 9

Neuron

Answer 9

• Functional unit of the Nervous System.
• Billions of neurons make up Nervous System & provide it with the ability to communicate internally with itself, and externally with the enviorment.
• Transmits impulses through both electrical and chemical signals.
• Form core of Nervous System (brain, spinal cord, peripheral glands)
• Composed of cell body, axon & dendrites.

Question 10

Cell body (Soma) of Neuron

Answer 10

Nucleus, lysosomes, mitochondria, Golgi complex

Question 11

Axon

Answer 11

Cylindrical projection from the cell body that transmits nervous impulses to other neurons and effector sites (muscles, organs)

Provides communication from brain & spinal cord to rest of body.

Question 12

Dendrites

Answer 12

Gather information from other structures and transport it back to the neuron.

Question 13

3 functional classifications of neurons:

Answer 13

• Determined by the direction of their nerve impulses
• Sensory (afferent) neurons
• Interneurons
• Motor (efferent) neurons

Question 14

Sensory (afferent) neurons

Answer 14

Respond to touch, sound, light and other stimuli & transmit nerve impulses from the effector sites (muscles, organs) to the brain and spinal cord.

• FROM muscles/organs TO the CNS.

Question 15

Interneurons

Answer 15

Transmit nerve impulses from one neuron to another.

“INTER” neurons - BETWEEN neurons

Question 16

Motor (efferent) neurons

Answer 16

Transmit nerve impulses FROM the brain & spinal cord TO the effector sites. (muscles, organs)

Question 17

Somatic nervous system

Answer 17

Nerves that serve outer areas of body & skeletal muscle.

Voluntary control of movement

Question 18

Autonomic nervous system

Answer 18

Neural input to the involuntary systems of the body.

AUTO - autopilot

No conscious control

Divided in to:
• Sympathetic System
• Parasympathetic System

Question 19

Sympathetic System

Answer 19

Ramps you up

Increases activation level of neurons for activity

Question 20

Parasympathetic System

Answer 20

Ramps your system down.

Decreases level of activation

Question 21

Sensory Receptors

Answer 21

Convert environmental stimuli (heat, sound, taste) into sensory information for the brain.

Consist of:
•GTO
•muscle spindles
•joint receptors

Divided in to:
•mechanoreceptors 
•nociceptors
•chemoreceptors
•photoreceptors

Question 22

Mechanoreceptors

Answer 22

Respond to mechanical pressure within tissues and transmit signals through sensory nerves. Senses distortion in body tissues.

Respond to outside forces: touch, pressure, stretching, sound waves, motion.

Question 23

Muscle spindles

Answer 23

Sensory receptors, run parallel to muscle fibers.

Sensitive to changes in muscle length, and rate of length change.

Senses muscle lengthening
Contracts the muscle in response (when excited)
Normal reaction to avoid injury (stretching too far, too fast)

Question 24

Golgi Tendon Organ (GTO)

Answer 24

Sensory receptors located where the skeletal muscle fibers attach to tendons.

Sensitive to changes in muscular tension and rate of tension change.

Senses muscle tension
Relaxes the muscle in response (when excited)
Normal reaction to avoid injury (to prevent muscle from being places under excessive stress)

Question 25

Joint receptors

Answer 25

Located around joint capsule.

Respond to pressure, acceleration & deceleration of the joint.

Act to signal extreme joint positions = prevent injury