Lec 15 - Respiratory System Intro

Question 1

there are different types of respiration, what are the two

Answer 1

cellular and external

Question 2

what is cellular respiration

Answer 2

intracellular metabolic process, derive energy from nutrient molecules, uses o2 and produces co2

Question 3

what is external respiration

Answer 3

sequence of events, exchange o2 and co2 between the environment and cellular tissues

Question 4

list some non respiratory functions of the respiratory system

Answer 4

vocalisation, regulation of acid base balance, thermoregulation, defence against infection, respiratory pump

Question 5

list the structures in the anatomy of the airways

Answer 5

nasal passages, pharynx, larynx, trachea, x2 bronchi, bronchioles, terminal bronchioles, alveoli

Question 6

what is the larynx

Answer 6

the voice box

Question 7

what is the laryngeal opening called

Answer 7

the glottis

Question 8

when air passes through the glottis what happens

Answer 8

vibrations produce sounds, lips/tongue/palate modify sounds

Question 9

describe the properties of the trachea and the larger bronchi

Answer 9

rigid, non muscular and contain cartilaginous rings

Question 10

what is the function of the trachea and bronchi being rigid, non muscular and having cartilaginous rings

Answer 10

the airways remain open

Question 11

what are the smaller bronchioles innervated by

Answer 11

the autonomic nervous system

Question 12

what are the small bronchioles sensitive to

Answer 12

hormones and local chemicals

Question 13

describe the smaller bronchioles

Answer 13

no cartilage, have smooth muscle

Question 14

what is the functional significance of the smaller bronchioles not having cartilage, being innervated by smooth muscles and sensitivie to hormones

Answer 14

regulate air flow to each cluster of alveoli

Question 15

what are alveolar walls made of

Answer 15

single layer of cells - type 1 alveolar cells

Question 16

alveolus are surrounded by a network of

Answer 16

pulmonary capillaries

Question 17

the air to blood barrier between the alveoli is how many micrometers

Answer 17

5

Question 18

the alveoli have a very ____ surface area with over 500 million alveoli

Answer 18

large

Question 19

what is the functional significance of alveoli having a large SA, thin layer of cells and close pulmonary capillaries

Answer 19

properties facilitate gas exchange

Question 20

alveolar type 2 cells account for 5% of the alveolar surface epithelium, what do they secrete

Answer 20

pulmonary surfactant

Question 21

what is pulmonary surfactant

Answer 21

a phospholipoprotein complex that facilitates lung expansion

Question 22

which cell type helps fight infection in the lungs

Answer 22

alveolar macrophages

Question 23

what are pores of kohn

Answer 23

minute pores in walls between adjacent alveoli

Question 24

what is the function of the pores of kohn

Answer 24

permit airflow between alveoli called collateral ventilation

Question 25

why are pores of kohn very important

Answer 25

if terminal conducting airways are blocked in disease, air can still reach them

Question 26

what is the pleural sac for

Answer 26

separating the lungs from the thoracic wall and other structures

Question 27

the pleural sac is _____ walled

Answer 27

double walled

Question 28

what is secreted by the pleural sac to aid in lubrication

Answer 28

intrapleural fluid

Question 29

what is pleurisy

Answer 29

inflammation of the pleural sac

Question 30

what is a sign of pleurisy

Answer 30

painful breathing due to friction rub

Question 31

what is a common cause of pleurisy

Answer 31

viral infection

Question 32

the visceral pleura adheres to the

Answer 32

surface of the lung

Question 33

the parietal pleura lines the

Answer 33

interior surface of the thoracic wall

Question 34

when the inspiratory muscles are activated, what do they do?

Answer 34

enlarge the thoracic cavity

Question 35

which nerve supplies the diaphragm

Answer 35

the phrenic nerve

Question 36

what is the major inspiratory muscle

Answer 36

the diaphragm

Question 37

when the diaphragm contracts during inspiration it

Answer 37

flattens

Question 38

when the diaphragm flattens what happens

Answer 38

it increases the vertical dimension of the cavity

Question 39

during quiet breathing, the diaphragm can descend up to ___ cm, during heavy breathing it can descend up to ___ cm

Answer 39

1cm, 10cm

Question 40

75% of enlargement of the thoracic cavity is accomplished by the diaphragm what is the other inspiratory muscle

Answer 40

the external intercostal muscles

Question 41

what innervates the external intercostal muscles

Answer 41

the external IC nerve

Question 42

the external IC fibres run down and forward, enlarging the cavity in 2 dimensions, which dimensions are these

Answer 42

lateral and antero-posterior dimension, elevating ribs and sternum up and out

Question 43

during active inspiration what happens that is different

Answer 43

the recruitment of accessory inspiratory muscles

Question 44

what are the accessory inspiratory muscles

Answer 44

the sternocleidomastoid and the scalenes

Question 45

what do the accessory inspiratory muscles do

Answer 45

raise sternum and elevate 1st 2 ribs, enlarging the upper part of thoracic cavity

Question 46

expiration at rest is

Answer 46

passive

Question 47

why is expiration at rest passive

Answer 47

inspiratory muscles inactive, + elastic recoil of lungs + gravity

Question 48

what are the two expiratory muscles

Answer 48

abdominal muscles e.g. rectus abdominus and obliques and internal IC muscles

Question 49

how do the abdominal muscles allow expiration

Answer 49

increase intra-abdominal pressure, increase force on diaphragm, decrease vertical dimension of thoracic cavity

Question 50

how do the internal IC muscles work

Answer 50

by moving the ribs down and in