Respiration Mechanisms

Question 1

Respiration Outline

Answer 1

Semi-voluntary (mainly sub-concious but can be controlled). Linked to multiple regions of brain

Question 2

External Respiration Def

Answer 2

Ventilation of breathing: moving of air in and out of lungs

Question 3

Internal Respiration Def

Answer 3

Exchange of carbon dioxide and oxygen between tissues and lungs. Cellular metabolism, anaerobic glycolysis and mitochondrial aerobic metabolism

Question 4

2 Types of Respritory Pressure at frest

Answer 4

Intra-alveolar and intra-pulmonary pressures. Intra-alveolar pressure = atmospheric pressure. Pulmonary pressure < atmospheric pressure (due to plural cavity suctions)

Question 5

Plural Cavity Def

Answer 5

Enclosed double membrane with (no contact with atmosphere).

Question 6

Atmospheric to mercury readings

Answer 6

1 atm = 760 mm Hg

Question 7

Eupnoea Def

Answer 7

Respiration at subconcious rest

Question 8

Inspiration outline

Answer 8

Active process, inspiratory muscles ,diaphragm and intercostal contract. Decreases pressure in lungs, air moves in from mouth to increase air volume

Question 9

2 Types of Inspiratory Muscles

Answer 9

Primary (diaphragm and intercostal) and accessory (sternocleidomastoid (lifts thorax), scalenes group (lifts lower ribs) and pectoralis minor)

Question 10

Rib Movements 1-6

Answer 10

Pump handle. Vertically up and down

Question 11

Rib movements 7-10 (external intercostal)

Answer 11

bucket handle. Up and out

Question 12

How does diaphragm movement change in deep inspiration

Answer 12

Diaphragm moves further down

Question 13

Nerves that innervate diaphragm

Answer 13

Phrenic nerve C3,C4, and C5. Damage to this region is fatal

Question 14

Acessory Muscles Outline

Answer 14

sternocleidomastoid (lifts thorax), scalens (lift lower ribs) and larynx intrinsic muscles (vocal cord abductors, post cricariotoids (supplied by laryngeal nerve). Symptom of paralysis: Inspiratory Stridor (high pitched breathing)

Question 15

Expiration (at subconscious rest) Outline

Answer 15

Muscles relax (no energy, elastic recoil). Pressure in lungs increases, volume of air decreases as it’s forced out of mouth

Question 16

Expiration (excited, conscious at rest) Outline

Answer 16

Active process. Internal intercostals (except interchondral) pull ribs down. Abdominal muscles pull ribs down, decreased space in thorax. Quadrilatus luborum pull ribs down

Question 17

Inspiratory Capacity

Answer 17

The volume of air in lungs from tidal volume + inspiratory reserve volume. Max amount of air lungs can hold

Question 18

Inspiratory reserve volume

Answer 18

Amount of air taken in above tidal volume when breathing deeply

Question 19

Expiratory Reserve volume

Answer 19

Amount of air pushed out of lungs after inspiratory reserve volume. Below tidal volume. Amount pushed out before returning to tidal

Question 20

Vital Capacity

Answer 20

Tidal volume + Inspiratory Reserve Volume + Expiratory reserve volume

Question 21

Functional Residual Capacity

Answer 21

Expiratory Reserve Volume + Residual volume

Question 22

Aveloar Pressure changes as breathing

Answer 22

During inspiration it decreases below atmospheric. During expiration it goes slightly above/ meets atmospheric pressure

Question 23

Pleural pressure changes as breathing

Answer 23

During inspiration it decreases significantly and during expiration it increases. Is always below atmospheric pressure due to suction of pleural cavity

Question 24

Method of increasing intrapulmonary pressure

Answer 24

Valsalva’s Maneuverblocking of airways (mouth and nose) and forcefully exhaling.

Question 25

Method of decreasing pulmonary pressure

Answer 25

Muller’s Manouver. After Valsava’s keeping airways blocked try breathing in. Increasing gravity, emphysea (loss in ling elascity) and pnuemothorax

Question 26

Way to measure intra plural pressure

Answer 26

intra-eospogial pressure

Question 27

Flow of Air Calculation

Answer 27

(Atmospheric Pressure - Intrapleural pressure) / airway ressistance

Question 28

Factor effecting airway ressistance

Answer 28

Radius of tube. PNS constricts SNS dilates

Question 29

Examples of increased ressistance in airway

Answer 29

Colds, asthma (histamine induced edema (swelling of tissues)), bronchitis (chronic thickened walls), emphysea (breakdown of aveolar walls), deficency in aveolar surface pressure (increase of negative intr-aveloar pressure, collapsed lung)