XIII: Breath Control

Question 1

Respiration controlled by the

Answer 1

Central nervous system

Question 2

What triggers the central nervous system in respiration

Answer 2

O2, CO2 alterations

Question 3

Increased respiratory rate

Answer 3

Tachypnea

Question 4

Decreased respiratory rate

Answer 4

Bradypnea

Question 5

Increased respiratory volume

Answer 5

Hyperventilation

Question 6

Decreased respiratory volume

Answer 6

Hypoventilation

Question 7

Respiratory center composed of

Answer 7

Neurons in the pons

And medulla oblontaga in brainstem

Question 8

3 structures to be distinguished

Answer 8

Dorsal respiratory group
Pneumotaxic center
Ventral respiratory group

Question 9

Function of the Dorsal respiratory group

Answer 9

Functions in inspiration (pacemaker)

Question 10

Signals in dorsal respiratory group

Answer 10

They increase progressively due to successive and continuous depolarizations

Question 11

How does the signal start in the dorsal respiratory group

Answer 11

It starts weak and progresses for 2 seconds

Question 12

What reaches the dorsal respiratory group

Answer 12

Efferent pathways that synapse at motor neuron of C3-C5 phrenic nerve roots (innervates the diaphragm)

Question 13

Signal, seconds during inspiration and expiration

Answer 13

Signal increases successively and progressively for 2 seconds (inhalation) and stops for 3 seconds (exhalation)

Question 14

Location of pneumotaxic center

Answer 14

Pons

Question 15

Function of pneumotaxic center

Answer 15

Inhibit the dorsal respiratory group

Limits inspiration to INCREASE RESPIRATORY RATE

Question 16

Why does the pneumotaxic center inhibit the dorsal respiratory group

Answer 16

To allow expiration to begin

Question 17

Ventral respiratory group function

Answer 17

Send signals to Dorsal Respiratory Group and Pneumotaxic Center for overstimulation TO INCREASE VENTILATION

Question 18

The apneustic center stimulates

Answer 18

Dorsal respiratory group

Question 19

Location of dorsal respiratory group

Answer 19

Nucleus of solitary tract that extends through medulla oblongata

Question 20

Location of pneumotaxic center

Answer 20

At parabrachial nucleus in pons

Question 21

Strong vs. weak pneumotaxic signal

Answer 21

Strong - 30-40 breaths/min

Weak - 3-5 breaths/min

Question 22

Location of ventral respiratory group

Answer 22

5mm anterolateral to dorsal respiratory group

Question 23

Function of ventral respiratory group

Answer 23

Remain inactive during silent breathing
But when respiratory requirements increase, respiratory signals from dorsal respiratory group reach the ventral respiratory group due to OVERSTIMULATION
Ventral respiratory group in charge of expiration signals to abdominal muscles during forced expiration

Question 24

Breathing control is

Answer 24

Autonomous/involuntary

Question 25

Autonomous signals via

Answer 25

Ventro-lateral tract

Question 26

Voluntary respiratory signals via

Answer 26

Cortico-spinal tract

Question 27

Direct effect on respiratory rate of

Answer 27

CO2 and H+

Question 28

Indirect effect on respiratory rate of

Answer 28

O2

Question 29

On what does O2 act on

Answer 29

Chemoreceptors in carotid and aortic bodies

Question 30

Chemosensitive zone is ONLY stimulated by

Answer 30

H+

Question 31

Why does not a high [H+] have a strong excitatory effect

Answer 31

Because its the CO2 reacting w/ H2O, producing HCO3- and H+ that has an excitatory effect on the CHEMOSENSITIVE AREA

Question 32

H+ impact central or peripheral chemoreceptors

Answer 32

Central chemoreceptors

Question 33

Peripheral chemoreceptors are located where

Answer 33

Outside the CNS

Question 34

To what are peripheral chemoreceptors sensitive to

Answer 34

O2 changes

Question 35

Carotid body fibers reach

Answer 35

Dorsal respiratory group at medulla oblongata

Question 36

Aortic bodies nerve fibers reach

Answer 36

Vagus nerve

Question 37

Which is most important in producing respiratory changes

Answer 37

CO2