Histology II: respiratory

Question 1

Name the parts of the respiratory tract.

Answer 1

nasal cavity, larynx, trachea, bronchial tree with different bronchi and bronchioles, and alveolar tree

Question 2

In addition to gas exchange the respiratory tract has several other functions: name them (5).

Answer 2

production of sound, 
sensation of smells, 
secretion of hormones, 
participation in cellular and immunological protection, 
and thermoregulation

Question 3

What type of organ is the trachea?

Answer 3

is a tubular organ

Question 4

What layers does the tracheal wall consist of?

Answer 4

three layers:
mucosa,
fibromusculocartilagineous layer,
adventitia.

Question 5

The tracheal mucosal layer in turn, consists of what layers?

Answer 5

ciliated pseudostratified columnar epithelium
lamina propria
the fibroelastic layer
submucosa

Question 6

Describe the tracheal innermost epithelial layer.

Answer 6

ciliated pseudostratified columnar epithelium that rests on a relatively thick basement membrane.

Question 7

Describe the tracheal lamina propria.

Answer 7

relatively thin consisting of loose connective tissue

Question 8

Describe the tracheal fibroelastic layer.

Answer 8

Separates the lamina propria from the submucosa.

It has longitudinally oriented elastic fibres.

Among the tubular organs the fibroelastic layer is characteristic only for the trachea.

Question 9

Describe the submucosa of the trachea.

Answer 9

consists of loose connective tissue, which is where the end portions of the tracheal glands also known as the tubuloalveolar compound glands, are present.

The ducts of the glands are open onto the surface of the epithelium.

Question 10

the free ends of tracheal cartilages are bridged by?

Answer 10

smooth muscle, the trachealis muscle

Question 11

The fibromusculocartilagineous layer of the trachea consists of?

Answer 11

horse-shoe shaped hyaline tracheal cartilages interconnected by connective tissue rich in elastic fibres.

Question 12

The lungs consist of?

Answer 12

the air conducting system and the interstitial tissue containing the blood vessels.

bronchial tree with different bronchi and bronchioles
and alveolar trees

Question 13

The wall of the bronchus consist of what 3 layers?

Answer 13

epithelial layer
fibromusculocartilagineous layer
tunica adventitia

Question 14

Describe the epithelial layer of the bronchal lumen.

Answer 14

ciliated pseudostratified columnar epithelium

becomes lower as the diameter of the bronchus decreases.

Question 15

The tunica mucosa of the bronchus is divided into what 4 layers?

Answer 15

epithial mucosal layer
lamina propria
muscularis mucosae or lamina muscularis
submucosa

Question 16

How does the fibromusculocartilaginous layer of the bronchus differ from that of the trachea?

Answer 16

unlike in the trachea, it consists of smaller plates of hyaline cartilage interconnected by connective tissue rich in COLLAGEN fibres.

Question 17

How does the fibromusculocartilaginous layer of the trachea differ from that of the bronchus?

Answer 17

unlike in the bronchus, it consists of horse-shoe shaped hyaline tracheal cartilages interconnected by connective tissue rich in ELASTIC fibres.

Question 18

Describe the outer layer of the bronchus.

Answer 18

tunica adventitia contains a large amount of adipose tissue.

Question 19

Describe bronchioles (bronchiolus).

Answer 19

diameter decreases continuously.
do not contain cartilages and glands.

lumen is lined with ciliated pseudostratified epithelium that gradually transforms into a simple ciliated columnar epithelium
(and then later when even smaller, to cuboidal).

Question 20

Describe the epithelial cell type in the smallest bronchioles.

Answer 20

simple cuboidal epithelium

cilia has gradually disappeared

Question 21

small bronchiole’s layers

Answer 21

epithelium
lamina propria
circular muscularis mucosae

Question 22

What does the bronchial tree end with, and then continue with?

Answer 22

terminal bronchioles (bronchiolus terminalis)

then the airways are continued as the alveolar tree.

Question 23

describe the parts of the alveolar tree

Answer 23

bronchiole (bronchiolus)
terminal bronchiole (bronchiolus terminalis)
respiratory bronchioles (bronchiolus respiratorius)
alveolar ducts (ductus alveolaris)
alveolar sacs (sacculus alveolaris)
alveoli

Question 24

Where does gas exchange happen?

Answer 24

in the walls of the alveoli

Question 25

What does the avian respiratory system consist of?

Answer 25

nasal cavity, larynx, trachea, syrinx and lungs

Question 26

What is a syrinx in birds?

Answer 26

syrinx or vocal organ of birds

located at the base of the trachea, where it divides into the bronchi

Question 27

basic steps of avian respiration?

Answer 27

air first into posterior air sacs,
then into the lungs
and finally into the anterior air sacs before it exits