Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

MS2 Respiratory > 9/11- Lung Embryology, Histology, Anatomy > Flashcards

9/11- Lung Embryology, Histology, Anatomy Flashcards

(48 cards)

Start Studying
1
Q

What are the main phases of lung development with their time periods?

A
  • Embryonic (26 d - 5 wks)
  • Pseudoglandular (6 - 16 wks)
  • Canalicular (17-28 wks)
  • Saccular (29 wks - birth)
  • Alveolar (36 wks - 4 yrs)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens during the Embryonic phase (26 d - 5 wks)?

A

MAJOR AIRWAYS

LRT begins as a laryngotracheal diverticulum from primitive pharynx; major airways begin to form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What happens during the Pseudoglandular phase (6 - 16 wks)?

A

TERMINAL BRONCHIOLE

Major airways to the level of the terminal (membranous) bronchi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens during the Canalicular phase (17-28 wks) ?

A

PULMONARY ACINUS

Pulmonary acini and vascularization develop; by week 24 respiratory bronchioles form & respiration is possible, but chances of survival are slim

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens during the Saccular phase (29 wks - birth)?

A

DISTAL AIRSPACES

Terminal sacs (alveolar ducts, alveoli) & adjacent lymphatic/capillary network develop, lined by type I & II pneumocytes; type II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens during the Alveolar phase (36 wks - 4 yrs)?

A

MATURE ALVEOLI

Newborn infant has only 1/6 to 1/8 of the adult number of alveoli; 95% of alveoli maturing after birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When does surfactant reach adequate/functional levels?

A

2 weeks before birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is seen here?

A

7 week fetus (pseudoglandular): three lobes (left) & primitive tubular structure (right)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is seen here?

A

18 week fetus (canalicular): pulmonary acini and vascular system form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is seen here?

A

4 day old infant; resembles adult lung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the functions of the airways?

A
  • Conduits for air
  • Moisturizing and warming functions
  • Evacuation of foreign material via mucociliary escalator
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where (what vertebral level) does the trachea branch into R/L main stem bronchi? What is this called?

A

Carina

  • T4 - T5
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which main bronchi is longer/narrower? more vertical?

A

Left: longer, narrower

Right: more vertical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

T/F: Aspirate material more frequently enters left vs. right lung

A

False! More into right (fatter, straighter)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How many lobar branches are there off the bronchi? Segmental bronchi?

A

Lobar bronchi: 3 on right, 2 on left

Segmental bronchi- 10 bronchopulmonary segments per lung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe bronchi histology

A
  • Cartilaginous airways
  • > 2 mm in diameter
  • Cartilage in walls that prevent their collapse (circumferential rings/plates)

Adventitia: Cartilagionous plates (as opposed to C-shaped cartilage in trachea) Submucosa: mucous glands

Muscular mucosa

Mucosa

1. Lamina propria

2. Respiratory epithelium: pseudostratified, ciliated columnar epithelium (90%) and goblet cells, neurosecretory (Kulchitsky) cells, clara, basal, and brush cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe bronchiole histology

A
  • < 2mm in diameter
  • Lack cartilage and submucosal glands
  • No goblet cells
  • Lined by simple rather than pseudostratified epithelium

Membranous (terminal) bronchioles:

  • 0.5 - 1 mm
  • smooth muscle wall
  • lamina propria
  • Ciliated cuboidal cells and nonciliated secretory (Clara) cells

Respiratory bronchioles:

  • 0.15-0.2 mm
  • have alveolar ducts and alveoli budding from their walls
  • Cuboidal cells
  • Epithelium and alveoli; no smooth muscle!
  • +/- cilia along one side; alveoli along the other
  • Give rise to alveolar ducts (composed only of alveoli)
  • Forms part of pulmonary acinus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

T/F: The right lung has 3 lobes while the left has 2

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which lobe does the lingula stem from?

A

Left upper lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lungs are covered by what?

Study These Flashcards
A

Visceral pleura

  • Parietal pleura covers the thoracic wall
21
Q

Define:

  • Pneumonectomy
  • Lobectomy
  • Segmentectomy
  • Wedge
Study These Flashcards
A

Resection of:

  • Pneumonectomy: entire lung
  • Lobectomy: single lobe
  • Segmentectomy: bronchopulmonary segment
  • Wedge: less than a segment
22
Q

What is a pulmonary lobule?

  • Shape
  • Airway components
  • Clinical correlations
Study These Flashcards
A

Smallest gross anatomic component

  • Polygonal shape, 1-2 cm diameter
  • Best visualized along pleural surface, bounded by connective tissue interlobular septa
  • Each lobule contains 3-5 terminal bronchioles and up to 30 pulmonary acini
  • Lobular architecture important for distinguishing major forms of emphysema
23
Q

What is seen here?

Study These Flashcards
A

Can easily see polygonal pulmonary lobules

  • Can see pleural puckering from metastatic carcinoma
  • Anthracosis (carbon pigment deposition)- especially around these septal units
24
Q

What is seen here?

Study These Flashcards
A

Normal lung

  • Alveolar septa
  • Clear alveolar spaces
25
Describe the trachea histology
**Adventitia:** C-shaped cartilage **Submucosa:** mucous glands Muscular mucosa **Mucosa** 1. Lamina propria 2. Respiratory epithelium: pseudostratified, ciliated columnar epithelium (90%) and goblet cells, neurosecretory (Kulchitsky) cells, clara, basal, and brush cells
26
What is the pulmonary acinus?
Functional unit of gas transfer (because lined by alveoli) - Pulmonary acinus = R.B. + A.D. + Alveoli
27
Which epithelium is shown on the left? right?
**Left:** bronchiole epithelium **Right:** tracheal and bronchi epithelium
28
Pick out the: - Membranous bronchioles - Respiratory bronchioles - Alveolar ducts
29
What are the cells of the alveoli (and their histological characteristics/functions)?
**Type I pneumocytes** - Flat squamous cells - Cover ~ 95% of alvoelar surface **Type II pneumocytes** - Cuboidal cells that serve two functions: 1. main cell type involved in alveolar repair 2. source of surfactant **Alveolar macrophages** - Loosely attached to epithelial surface or free in alveolar space - Phagocytic function
30
What is surfactant?
Phospholipid that decreases alveolar surface tension; facilitating alveolar expansion
31
Describe the content of alveolar interstitium
- Capillaries - Elastic fibers - Myofibroblasts (support alveolar framework)
32
What is the alveolar-capillary barrier?
Thinnest point for gas diffusion (0.2-2.5 um)
33
What is this?
Type I pneumocyte
34
What is this?
Type II pneumocyte
35
What are Pores of Kohn?
Develop after birth; connect adjacent alveoli - Involved in collateral ventilation - 13-21 per alveolus
36
What are Lambert's canals?
Direct communication between airway (bronchiole) and adjacent alveoli - Involved in collateral ventilation
37
**T/F:** the lung has a dual vascular supply?
True
38
What are pulmonary arteries? Where do they come from? Where do the go?
Accompany airways to lung periphery - Form capillary network around alveoli - Bring deoxygenated blood from right side of heart - About the same size of adjacent bronchiole - Dual elastic lamina
39
What are bronchial arteries? Where do they come from? Where do the go?
Systemic in origin arising from intercostal arteries and aorta - Form plexus around trachea and bronchial wall as far as respiratory bronchioles - Also supplies visceral pleura (supply nutrition to airways/lung)
40
What are pulmonary veins? (where do they go)
Return oxygenated blood to the heart - Travel with interlobular septa - Single elastic lamina
41
What are bronchial veins? (where do they go)
Deoxygenated blood to systemic circulation via azygos and intercostal veins
42
What is seen here?
Membranous bronchiole with accompanying arteriole - "Bronchovascular channel" - Observe that they're about the same size
43
How to distinguish between pulmonary artery and vein?
Artery has two elastic lamina
44
What is seen here?
**Left:** pulmonary artery **Right**; pulmonary vein
45
Describe the lymphatics of the lung
Two systems: **1. Superficial lymphatic drainage** - Present along pleural surface **2. Deep (intrapulmonary) lymphatic drainage** - Present adjacent to bronchovascular bundle and along interlobular septa Connections exist between both forms of lymphatic drainage
46
What is seen here?
Membranous bronchiole with pulmonary artery (bronchovascular channel) - Can see lymphatic channels (intraparenchymal)
47
What is seen here?
Lymphatic channels (filled with metastatic cancer)
48
(:

MS2 Respiratory (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions