Nervous System

Question 1

master control and communication system

Answer 1

Nervous System

Question 2

Nervous system three overlapping functions:

Answer 2

a. SENSORY INPUT
b. INTEGRATION
c. MOTOR OUTPUT

Question 3

uses its millions of sensory receptors to monitor changes occurring both inside and outside the body

Answer 3

SENSORY INPUT

Question 4

processes and interprets the sensory input and decides what should be done at each moment

Answer 4

INTEGRATION

Question 5

causes a response, or effect, by activating muscles or glands

Answer 5

MOTOR OUTPUT

Question 6

Aka “Glial cells”

Answer 6

Neuroglia

Question 7

✓Supports the nerve cells/ neurons
✓Non-excitable cells
✓Support cells

Answer 7

Neuroglia

Question 8

Macrophages in the CNS

Answer 8

MICROGLIA

Question 9

Defense against infection et injury

Answer 9

MICROGLIA

Question 10

Form & maintain myelin sheath in the CNS

Answer 10

OLIGODENDROCYTES

Question 11

✓Star-shaped cells
✓Most numerous/ abundant

Answer 11

ASTROCYTES

Question 12

Fnxs:
a. Provide structural support to the CNS
b. Take up extracellular K ion
c. Regulate the extracellular concentration of
neurotransmitter
d. Glycogen storage
e. Capable of cell multiplication/ replacement
gliosis

Answer 12

ASTROCYTES

Question 13

Located in the ventricles et central canal of the
spinal cord

Assist in the circulation of cerebrospinal fluid (CSF)

Answer 13

EPENDYMAL CELLS

Question 14

form the myelin sheaths around nerve fibers in the PNS

Answer 14

SCHWANN CELLS

Question 15

act as protective, cushioning cells for peripheral neuron cell bodies

Answer 15

SATELLITE CELLS

Question 16

(+) nucleus, cytoplasm with typical organelles

Answer 16

CELL BODY

Question 17

Highly branched structures that carry impulses to the cell body

Answer 17

DENDRITES

Question 18

Conducts away from cell body towards
another neuron, muscle/ gland

Emerges at cone-shaped axon hillock

Answer 18

AXON

Question 19

Contain synaptic vesicles that can release neurotransmitter

Answer 19

AXON TERMINALS

Question 20

whitish, fatty material which has a waxy appearance

protects and insulates
the fibers

increases the transmission rate of nerve impulses

Answer 20

MYELIN SHEATHS

Question 21

gaps, or indentations

Facilitates Saltatory Conduction

Answer 21

NODES OF RANVIER

Question 22

Collection of cell bodies inside the CNS

Answer 22

NUCLEI

Question 23

Collection of cell bodies outside the CNS

Answer 23

GANGLIA

Question 24

Bundles of nerve fibers running through the CNS

Answer 24

TRACTS

Question 25

Bundles of nerve running through the PNS

Answer 25

NERVES

Question 26

consists of dense collections of myelinated fibers (tracts)

Answer 26

WHITE MATTER

Question 27

Contains mostly unmyelinated fibers and cell bodies

Answer 27

GRAY MATTER

Question 28

Convey impulses into the CNS Examples: a. Cutaneous sense organs b. Proprioceptors

Answer 28

SENSORY (AFFERENT)

Question 29

Convey impulses from brain/ SC out through PNS to effector (muscle or organs)

Answer 29

MOTOR (EFFERENT)

Question 30

Aka “associated neurons” Most are within the CNS Transmit impulses between neurons, such as between sensory and motor neuron

Answer 30

INTERNEURON

Question 31

Motor, pyramidal, purkinje cell Have several/ many dendrites and 1 axon Most common type in the CNS

Answer 31

MULTIPOLAR

Question 32

One dendrite and one axon Example: a. Retina of the eye b. Inner ear c. Nose

Answer 32

BIPOLAR

Question 33

Have fused dendrite and axon Sensory neurons of spinal nerves Touch and pain sensory neuron

Answer 33

UNIPOLAR

Question 34

Two major functional properties: a. Irritability b. Conductivity

Answer 34

Nervous Physiology

Question 35

also called a nerve impulse in neurons

Answer 35

Action Potential

Question 36

An increase in membrane potential of 15-30 mV usually is required to cause an explosive development of action potential

Answer 36

All-or-None Principle

Question 37

Overshoot period/ phase Cause: a. Fast opening of voltage voltage gated Na channel channel (opening of activation gate) Na influx Charge of the cell becomes positive

Answer 37

DEPOLARIZATION

Question 38

Cause: a. Fast closure of voltage-gated Na channels (closure of inactive gates) K efflux Charge of the cell becomes negative

Answer 38

REPOLARIZATION

Question 39

Aka “Positive after potential” Cause: a. Slow late closure of voltage gated K channels Charge of the cell becomes more negative

Answer 39

HYPERPOLARIZATION

Question 40

A state wherein a (+) charge outside & (-) charge inside the cell Activation of Na-K ATPase Pump The charge of the cell returns to normal membrane potential a. RMP of nn= -70 Mv b. RMP of skeletal ms= c. RMP of cardiac ms= - d. RMP of GI tract= -56_56 mV

Answer 40

RESTING MEMBRANE POTENTIAL

Question 41

Period during which a 2nd AP cannot be elicited even with a strong stimulus At the peak of depolarization

Answer 41

ABSOLUTE REFRACTORY PERIOD

Question 42

Starts at 1/3 o repolarization onwards Stronger than normal stimulus elicits new AP

Answer 42

RELATIVE REFRACTORY PERIOD