Functional histology of the lungs

Question 1

what are the three principle compartments of the respiratory system

Answer 1

• Conduction zone
• Respiratory zone
• Musco-elastic ventilation apparatus

Question 2

What does the conduction zone do

Answer 2

Conditions inhaled air

Question 3

What does the respiratory zone do

Answer 3

Site of gas exchange

Question 4

What does the music-elastic ventilation apparatus do

Answer 4

Drives ventilation

Question 5

What does air come in through and what happens here

Answer 5

Nasal cavity

-air gets swirled around

Question 6

Where does air go after the nasal cavity

Answer 6

Nasopharynx and then the trachea through the voice box

Question 7

What is the gas exchange region in the lungs called

Answer 7

Distal respiratory tree

Question 8

What are airways kept open by and why

Answer 8

Bony/cartilaginous scaffolds

-To cope with changing pressure

Question 9

What do turbinate bone do an where are they

Answer 9

In the nasal cavity and they form narrow passageways that create turbulence so drive air in and out of the sinuses because opening of sinuses is very small

Question 10

How is temperature adjustment and moisturizing enhanced

Answer 10

Due to large venous plexus in the submucosa

Question 11

How are large particles prevented entry

Answer 11

By vibrissae (small hairs at entry to nasal cavity)

Question 12

What is the epithelium of the respiratory tract to the bronchioles

Answer 12

Respiratory epithelium

Question 13

What is below the epithelium

Answer 13

Mucosa has a sponge like epithelium due to the extensive venous plexus

Question 14

What does the venous plexus do

Answer 14

Mediate exchange of moisture with the air; their filling status also relates the flow of air through the nasal cavities

Question 15

What is on top of the nasal cavity

Answer 15

Olfactory elithelium

Question 16

What does the olfactory epithelium do

Answer 16

Conveys the sense of smell

Question 17

What do the cilia on the olfactory epithelium carry

Answer 17

Odorant receptors

Question 18

what do the central processes of the olfactory processes of the olfactory receptor neurons in the olfactory epithelium unite to form

Answer 18

Nerve bundles that pass through the crifriborm plate (which collectively constitute the olfactory nerve) and enter the olfactory bulb

Question 19

What is the trachea kept open by

Answer 19

Horse shoes shaped cartilage

Question 20

What glands does the trachea have and where

Answer 20

Seromucous glands in the submucosa

Question 21

What completes the rings which are partially formed by the cartilage

Answer 21

Smooth muscle

Question 22

What does respiratory epithelium consist of

Answer 22

Pseudostratified, ciliated epithelium of varying thickness (depending on region) with mucous producing goblet cells

Question 23

What areas ave additional seromucuous glands in their submucosa

Answer 23

Trachea

Question 24

What is mucociliary clearance

Answer 24

Mucus getting transported towards the pharynx by constantly beating cilia

Question 25

What does bronchus haven its wall

Answer 25

cartilage

Question 26

what is the lumen of bronchus bordered by

Answer 26

Respiratory epithelium

Question 27

When there is an incomplete ring of smooth muscle located between the epithelium and cartilage, what may be present

Answer 27

Submucosal glands

Question 28

what does the presence of cartilage mean

Answer 28

It is a bronchus

Question 29

How are the bronchioles different from bronchi

Answer 29

- No cartilage in its wall - Epithelium is smaller and the cells are not columnar anymore - Fewer goblet cells

Question 30

What is the epithelium of the smaller bronchioli like

Answer 30

Cells become cuboidal and the cells consist of ciliated and non-ciliated club cells

Question 31

What is the role of club cels

Answer 31

Protective role as they generate serous secretions

Question 32

What surround the epithelium in smaller bronchioli

Answer 32

complete ring of smooth muscle

Question 33

What is the ration of muscle ring thickness to luminar diameter like in bronchioli than bronchi

Answer 33

Higher

Question 34

What does the bronchiolar constriction induce

Answer 34

High airway resistance

Question 35

What do terminal bronchioles give rise to

Answer 35

Respiratory bronchioles that have cuboidal epithelium and alveoli built in their walls

Question 36

What does the connective tissue of the alveoli and the lower airways contain

Answer 36

Numerous elastin fibres

Question 37

What is the blood air barrier in the alveoli built of

Answer 37

Ultra thin walls of capillary endothelium and type 1 cells

Question 38

Where is the blood supply to the alveolar capillary networks from

Answer 38

Pulmonary circulation (which are elastic to distal part)

Question 39

What are pulmonary arteries like

Answer 39

Elastic arteries with comparatively thin walls

Question 40

What are do the larger pulmonary arteries accompany

Answer 40

bronchi and bronchioli

Question 41

What do the bronchi have their own blood supply from

Answer 41

aorta which are muscular

Question 42

What are the bronchial arteries like

Answer 42

Small strong muscular wall like elastin

Question 43

Why are surfactants used

Answer 43

Because in a space of such a small diameter as an alveolus, any water on the alveolar surface would exert strong capillary forces which would inhibit the expansion of the lung

Question 44

What do surfactants do

Answer 44

Reduce surface tension

Question 45

Where are the lymph vessels of the lung's lymphatic drainage system found

Answer 45

In the septa next to the vessels of the pulmonary circulation

Question 46

What do the lymph vessels in the lung drain into

Answer 46

A series of major lymph nodes along the trachea

Question 47

Where are there also a network of lymph vessels

Answer 47

Interstitial layer adjacent to the pleura

Question 48

Where are tonsils found

Answer 48

In oral and nasal cavity

Question 49

What are tonsils

Answer 49

Antigen presentation sites which have access to the airways

Question 50

How many tonsils are there in nasal cavity

Answer 50

5

Question 51

What is Waldeyer's ring

Answer 51

Ring of tonsils at the anterior pharynx which are basically aggregates of lymph follicles

Question 52

What do the mucus of the airways contain

Answer 52

immunoglobins

Question 53

What are the primary line of defense in alveoli

Answer 53

alveolar macrophages