L7 Lower airways

Question 1

Describe the cartilage rings of the trachea in different species

Answer 1

mammals have incomplete rings dorsally

birds have complete and overlapping cartilage rings

Question 2

What connects the cartilages of the trachea

Answer 2

annular ligament

Question 3

Which muscle forms the roof of the trachea

Answer 3

trachealis

Question 4

Describe relative tracheal shapes of dogs/ ox/ horse

Answer 4

dog’s & horses compressed dorsoventrally.

Cow’s compressed laterally.

Horses cartilages kinda overlapping

Question 5

What is the carina

Answer 5

a cartilage situated at the point where the trachea (windpipe) divides into the two bronchi.

Question 6

what kind of receptors provide sensory innervation to the trachea and some parts of the lungs

Answer 6

mechanoreceptors

Question 7

describe the branching on the bronchial tree

Answer 7

trachea > bronchi > bronchial tree (= principle, lobar 2ary bronchus, segmental 3ary bronchus, small bronchus, bronchiole terminal bronchiole ….

Question 8

Describe the branching beyond the terminal bronchiole

Answer 8

there is no further branching.

Bronchiole becomes respiratory alveolar, alveolar duct, alveolar sac

Question 9

how does the cartilages differ between the trachea and bronchi

Answer 9

bronchi have cartilaginous plates instead of rings

Question 10

what is a bronchopulmonary segment

Answer 10

segment of bronchus and the lung tissue that it ventilates

Question 11

What is a pulmonary acinus

Answer 11

respiratory bronchiole and the lung tissue that it ventilates (many alveoli in the walls of bronchioles, alveolar ducts, alveolar sacs)

Question 12

What primitive foetal structure is the respiratory parenchyma derived from?

Answer 12

endoderm

Question 13

Describe the cartilaginous rings of a birds trachea

Answer 13

complete rings

palpate on R neck

Question 14

where does a bird’s trachea bifurcate

Answer 14

dorsal to base of heart

Question 15

Where is a birds syrinx?

Answer 15

point of tracheal bifurcation

Question 16

What is the pessulus?

Answer 16

wedge shaped cartilage at point of tracheal bifurcation

Question 17

Caudal to the pessulus in a birds RT, where can tympanic membranes be found?

Answer 17

lateral and medial walls of the principle bronchi

Question 18

describe the branching of a bird/s bronchi

Answer 18

2x principle bronchi > secondary bronchi > branch into tertiary parabronchi which anastomose with each other

Question 19

Describe the morphology of the respiratory capillaries in birds

Answer 19

air capillaries form loops from walls of parabronchi and back to parabvroncih

Question 20

which bronchi do the airsacs connect to?

Answer 20

2ard bronchi

Question 21

do birds have a diaphragm

Answer 21

no

Question 22

what is the location of birds airsacs

Answer 22

between thoracic and abdominal viscera

Question 23

name the cranial airsacs

Answer 23

From cranial to caudal, 
Cervical (unpaired)
Clavicular (unpaired) 
cranial thoracic (paired) 
some species also have cervicocephalic

Question 24

name the caudal air sacs

Answer 24

caudal thoracic (paired)
abdominal (paired)

Question 25

what is the function of the cranial air sacs

Answer 25

receive stale air from the lungs and expel back through trachea

Question 26

What is the function of the caudal airsacs

Answer 26

supply fresh air to lungs

Question 27

what happens in a bird upon inspiration

Answer 27

air flows into lungs and caudal air sacs which pushes stale air from lungs into cranial air sacs

Question 28

what haps in a bird upon expiration

Answer 28

air sacs are compressed and fresh air pushed from caudal airsacs into lungs and air from cranial airsacs into the trachea for expulsion