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Flashcards in Histology Pulm Deck (51)
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1
Q

The ____ is the most anterior part of the nasal cavity and its lining is the continuation of the skin of the face, which is ____ epithelium. The epithelium contains ___ used to trap dust particles.

A

Vestibule
Stratified squamous
Vibrissae

2
Q

The ___ segment of the nasal cavity occupies most of the volume of the nasal cavity. The lining consists of 2 layers. Describe them.

A

Respiratory

  1. Ciliated pseudostratified columnar epithelium with goblet cells faces the lumen. Contains 5 cell types
  2. Underlying lamina propria attached to periosteum or perichondrium. Contains venous plexus of inferior and medial nasal conchae (allergic rxns when these vessels are engorged)
3
Q

What are the 5 cell types in the Ciliated pseudostratified columnar epithelium of the respiratory segment of the nasal cavity?

A
  1. Ciliated cells: tall columnar cells. Numerous in conducting parts. Move mucous.
  2. Goblet cells: mucous secretion.
  3. Basal cells: differentiate into other cells
  4. Brush cells: receptor cells that have short blunt microvilli.
  5. Small granule cells: homologous to enteroendocrine cells of the GI tract
4
Q

What two cell types form the mucociliary apparatus?

A

Goblet cells

Ciliated cells

5
Q

Respiratory segment of the nasal cavity:

Medial wall vs. lateral wall

A

Medial: smooth
Lateral: forms folds called turbinates or conchae

6
Q

What is the function of nasal turbinates/conchae?

A

Increase surface area for warming and moistening of incoming air
-also cause air turbulence which allows for conditioning of air

7
Q

How is olfactory epithelium different from the rest of the respiratory epithelium?

A

It contains neurons and lacks goblet cells

8
Q

What kinds of cells does the olfactory epithelium contain?

A
  1. Olfactory cell
  2. Basal cell
  3. Supporting/sustentacular cell
9
Q

Describe supporting/sustentacular cells of olfactory epithelium

A

most numerous
tall columnar cells
apical nuclei, covered with microvilli
mechanical and metabolic support for olfactory cells through production of odorant-binding proteins

10
Q

Describe olfactory cells

A

Bipolar neuron

spans entire thickness of epithelium

11
Q

Describe basal cells of the olfactory epithelium

A

Progenitor cells

12
Q

____ cells are among the very few neurons in our body that are actively replaced in the postnatal development.

A

Olfactory

13
Q

The ___ of the olfactory epithelium is unusually thick and contains the following 3 structures:

A

Lamina propria
1. Bowmans glands
2. Unmyelinated axons
Venous sinuses

14
Q

Describe Bowmans glands

A

Branched tubuloalveolar serous secreting glands
Watery secretion
Trap odiferous substances
Washing of surfaces so new smells can be detected

15
Q

Most of the larynx is lined with ___ epithelium that changes to ___ epithelium in the areas of high abrasion (i.e. Epiglottis, vocal cords, etc.)

A

Ciliated pseudostratified columnar

Stratified squamous

16
Q

The trachea connects the ___ to the ____.

The larynx connects the ___ to the ___

A
  1. Larynx to bronchi

2. Pharynx to trachea

17
Q

The mucosa of the trachea is composed of ____ epithelium and ___

A

Ciliated pseudostratified columnar epithelium and lamina propria

18
Q

Respiratory epithelium is ____

A

Ciliated pseudostratified columnar epithelium

19
Q

In smokers, the basement membrane becomes ___ due to constant irritation of the mucosa.

A

Thickened

20
Q

What are the cell types found in the epithelium of the trachea?

A
  1. Ciliated cells
  2. Goblet cells
  3. Brush cells
  4. Small granule cells
  5. Basal cells
21
Q

The boundary between the mucosa and submucosa of the trachea is defined by ___

A

An elastic membrane

22
Q

Describe the submucosa of the trachea

A

Loose CT
Seromucous glands whose ducts extend through the lamina propria and open on the surface of the epithelium where secretory products (mostly glycoproteins) are distributed along the surface

23
Q

The submucosa of the trachea is separated from its adventitia by ___, which are ___ shaped and connected to the ___ muscle (which is composed of smooth muscle fibers). This muscle layer is not continuous and is only found on the ___ side of the trachea.

A

Tracheal cartilages
C
Trachealis
Posterior

24
Q

The ___ layer of the trachea contains larger blood and lymphatics vessels and nerves

A

Adventitia

25
Q

Bronchi are characterized by the presence of ___ and a continuous layer of ____

A

Cartilaginous plates

Smooth muscle

26
Q

Try or false:

Bronchi epithelium and trachea epithelium are identical

A

True

27
Q

____ formed by hyaline cartilage covered with perichondrium descend into minor bronchi. When these disappear, the air tubule is designated as a bronchiole.

A

Discontinuous cartilaginous plates.

28
Q

Adventitia of bronchi is composed of dense CT that is adjacent to that of ___

A

Pulmonary a. and lung parenchyma

29
Q

Bronchioles are usually ___ in diameter

A

1 mm or less

30
Q

True or false:

Walls of bronchioles contain cartilage and glands

A

False

31
Q

Branching pattern of larger bronchioles:

A

Larger bronchioles - terminal bronchioles - respiratory bronchioles - alveoli

32
Q

___ bronchioles supply pulmonary acini

A

Terminal

33
Q

Terminal bronchioles are lined with ___ epithelium that is formed by 2 cell types ____

A

Simple cuboidal

  1. Cuboidal or low columnar cells with cilia (assist in transport of secretions up the bronchioles. Outnumber other types of cells)
  2. Club cells (specialized secretory cells in apical portion, lipo-proteins and club cell proteins)
34
Q

As the respiratory bronchioles proceed distally what happens?

A

More and more alveoli open into the bronchioles until there is nothing left of the wall
This becomes the alveolar duct

35
Q

Spaces surrounded by clusters of alveoli are called ___

A

Alveolar sacs

36
Q

___ represent the major site of gas exchange. Presence of these increase the internal surface area of the lung, which in a human is close to ____ meters squared

A

Alveoli

75

37
Q

The capillaries and connective tissue of the alveolar septum constitute the ___, within which is found the richest ____ in the body

A

Interstitium

Capillary network

38
Q

The walls of the capillaries in the alveolar septa are ___ and lined with____

A

Continuous (NOT fenestrated)

Very thin endothelial cells

39
Q

The air spaces of the alveolus are lined with 2 main cell types:

A
  1. Type I Pneumocyte

2. Type II Pneumocyte

40
Q

Describe the Type I Pneumocyte

A
  • flattened, squamous
  • 95% of alveolus surface
  • joined to each other by occluding junctions
  • not capable of mitosis
  • basal laminae are fused with endothelial cells of tight capillaries bound by occluding junctions
41
Q

What cells represent the air-blood barrier? Gas exchange occurs primarily here

A

Type I Pneumocyte
Endothelial cells
Fused basal laminae

42
Q

Describe the Type II Pneumocyte

A

AKA septal cell or type II alveolar cell

  • large, rounded, cuboidal
  • secretory cell
  • multilamellar bodies
  • progenitors for type I Pneumocyte
  • more concentrated in septal junctions
  • capable of mitosis
43
Q

What are multilamellar bodies?

A

Contain surfactant which is released by exocytosis to reduce surface tension and prevent collapse of alveoli

44
Q

In premature infants the levels of surfactant synthesis may be insufficient.
Alveoli may collapse
What is this called?

A

Respiratory distress syndrome (RDS)

45
Q

How do you reduce the risk of RDS in premature infants?

A

Give exogenous surfactant at birth

46
Q

What do alveolar pores do?

A

Located in interalveolar septa
Connect neighboring alveoli
Equalize air pressure
Provide collateral air circulation of bronchioles is obstructed

47
Q

Alveolar macrophages are derived from ___. They are present inside the ____ and ____

A

Blood monocytes

Septal walls and alveolar spaces

48
Q

More than _____% of deaths worldwide are due to cigarette smoking.

A

85

49
Q

The 2 most common types of malignant tumors found in the lungs are ____ and ____

A

Non-small-cell carcinoma

Small-cell carcinoma

50
Q

____ is the most common lung cancer (75 %
of all malignant tumors of the lung), which is a fast-developing, usually metastasizing tumor. This type of lung cancer occurs in both smokers and non-smokers. The two most common types are ___ and ___

A

Non-small-cell carcinoma
Squamous cell carcinoma
Adenocarcinoma

51
Q

___ are the most aggressive and rapidly growing lung cancers. They are also highly malignant and constitute up to 20 % of
lung tumors. They are strongly related to cigarette smoking with only 1 %
occurring in non-smokers. Oten discovered after it has spread extensively. They are often
called ____

A

Small cell carcinoma

“Oat cell” carcinoma