HMS: Nervous System

Question 1

Nervous System

Answer 1

A network of nerves made up of neurons that transmits information w/in the body.

Question 2

Neuron

Answer 2

A cell that is the functional unit of the nervous system.

Question 3

Dendrites

Answer 3

Part of the neuron that receives info from other neurons or the environment.

Question 4

Axon

Answer 4

Part of the neuron that is the pathway for messages (electrical impulses/ action potentials) to be sent to other neurons, muscles, and glands.

Question 5

Neurolemma

Answer 5

Part of the neuron that is the outermost layer of nerve fiber in the PNS. It serves a protective function. Myelin Sheath lies beneath.

Question 6

Synaptic Terminals

Answer 6

Part of the neuron that is a junction where messages (electric impulses/ action potentials/chemical) are transferred from one neuron to another, and to non-neuronal cells like those in muscles & glands.

Question 7

Action Potential

Answer 7

An electro-chemical wave that travels along the axon, provoking a release of neurotransmitter molecules.

Question 8

Effector Sites

Answer 8

Muscles, glands, and organs that receive messages from the CNS.

Question 9

Electrolyte

Answer 9

Electrically charged minerals & water that facilitate the transmission of nerve impulses throughout the body. Four primary: sodium, potassium, magnesium & water.

Question 10

CNS

Answer 10

Brain & Spinal cord responsible for coordinating the activity of all the parts of the body.

Question 11

PNS

Answer 11

The network of nerves that connect the CNS to the rest of the body and the environment. The PNS allows the CNS to receive sensory input and send a response.

Question 12

Number of CNS nerves

Answer 12

12 cranial nerves & (31 pair of spinal nerves belong to PNS)

Question 13

Afferent pathway

Answer 13

PNS sends up sensory information to the CNS

Question 14

PNS Spinal Nerves, number and loc.

Answer 14

Cervical (c1-c7)
Thoracic (t1-t-12)
Lumbar (l1-l5)
Sacral (s1-s5)
Coccygeal (1)

Question 15

Efferent Pathway

Answer 15

Also known as motor pathway, it is the way the CNS sends messages down through the rest of the body.

Question 16

Interneurons

Answer 16

Located only w/i the CNS, they transmit impulses between afferent & efferent neurons.

Question 17

Sensory Receptors

Answer 17

Structures located throughout the body that convert environmental stimuli into sensory information, send this information via the afferent pathway to the CNS, which uses this information to form a response. Types include!: mechano, noci, photo & chemo.

Question 18

Mechanoreceptors

Answer 18

Sensory receptors that respond to mechanical forces (touch/ pressure).

Question 19

Nociceptors

Answer 19

Sensory receptors that respond to pain.

Question 20

Chemoceptors

Answer 20

Sensory receptors that respond to chemical interaction (smell/ taste).

Question 21

Photoceptors

Answer 21

Sensory receptors that respond to light (vision).

Question 22

Somatic Nervous System

Answer 22

Consists of nerves that serve the outer areas of the body & skeletal muscles that is largely responsible for voluntary control of movement.

Question 23

PNS Classification Tree

Answer 23

PNS consists of two major divisions:

Sensory Nerves (afferent) &

Motor Nerves (efferent)

within Motor Nerves:

Somatic & Autonomic Nervous Systems

the Autonomic Nervous System is divided into:

Sympathetic & Parasympathetic Sys.

Question 24

Autonomic Nervous System

Answer 24

Supplies neural input to organs that govern the involuntary processes of the body (blood circ., digestion, etc.)

Question 25

Sympathetic Nervous System

Answer 25

Responsible to increase neural activity and signals endocrine organs to release hormones like adrenaline to increase heart rate, breathing and alertness in anticipation of heightened activity. Fight or Flight.

Question 26

Parasympathetic Nervous System

Answer 26

Responsible to to decrease neural activity by suspending the release of excitatory hormones, putting the body in a more relaxed state. Rest & Digest.

Question 27

Primary functions of Nervous System

Answer 27

Provide Sensory, Integrative & Motor function.

Question 28

Muscle Spindles

Answer 28

Mechanoreceptors within muscles that run PARALLEL to the muscle fibers and are sensitive to changes in muscle LENGTH & rate of change.

Question 29

Stretch Reflex

Answer 29

When a muscle is stretched the mechanoreceptor muscle spindles are also stretched and report the length and rate of stretch to the CNS, causing the CNS to send a message ordering the muscle to contract in order to prevent excessive lengthening/ injury.

Question 30

Golgi Tendon organ

Answer 30

Mechanoreceptors located at the point where skeletal muscles insert into the tendons that are sensitive to change in muscular TENSION & the rate of tension change. Activation causes muscle to relax to prevent excessive stress/ injury.

Question 31

Joint Receptors

Answer 31

Mechanoreceptors in and around joint capsules that respond to pressure, acceleration & deceleration of the joint. Will signal extreme joint positions and initiate an automatic inhibitory response to surrounding muscle if too much stress is placed on that joint.

Question 32

Neuroplasticity & Neurocircuitry

Answer 32

The concept that the brain will continue to change & grow by reforming neural pathways through lifespan. Neurocircuitry is the interconnection of neurons in the brain & spinal cord.

Question 33

Stages in Motor Skill Development

Answer 33

Stage 1: Cognitive. Know goals of the skill & dev. movement strategies, but can only inconsistently perform. Stage 2: Associative. Practice refines skill, performed w/ less error. Stage 3: Autonomous. Mastered & can independently modify the skill.