BIOMED - Histology

Question 1

What are the 2 physiologic divisions of the respiratory tracts and what are there functions?

Answer 1

Conducting: transporting air to where it can undergo gas exchange. Respiratory: gas exchange!

Question 2

What cell type makes up respiratory epithelium?

Answer 2

Ciliated pseudostratified columnar epithelium w/ goblet cells

Question 3

What are the main functions of the respiratory epithelium and the lamina propria?

Answer 3

Warm and humidify air Aid in immune response Trap particles in mucus and cilia to propel them out

Question 4

What are the 4 layers of the trachea and what is generally found in each?

Answer 4

Starting from inner to outer: mucosa (epithelium and lamina propria) Submucosa (glands) Trachealis muscle / cartilage layer Adventitia (connective tissue)

Question 5

Is the anterior or posterior region of the trachea more cartilaginous? And which is more muscular?

Answer 5

Anterior 2/3 is cartilage. Posterior 1/3 is trachealis muscle.

Question 6

What type of cartilage will you find in the trachea?

Answer 6

Hyaline

Question 7

The epithelial cells of the bronchus are __________ transitioning to _________.

Answer 7

Respiratory epithelium (as before, pseudostratified) Transitioning to simple columnar.

Question 8

Smooth muscle is located in between what layers in the bronchus?

Answer 8

Just beyond the epithelial layer and superficial to the submucosa

Question 9

How is the cartilage organized differently in the bronchus than it is in the trachea?

Answer 9

Cartilage is arranged in discs in the bronchus unlike in the trachea where it is a ring.

Question 10

What part of the respiratory tract are Clara cells located and what is their function?

Answer 10

Lower respiratory tract, Bronchioles 1. Secretes a substance (surfactant) that decreases surface tension to prevent collapse of the airway (basically makes the lumen less sticky so it doesn’t stay stuck to itself and prevent an open airway). 2. Secretes substances which combat irritants. 3. Stem cells.

Question 11

What are the 3 primary cell types of the alveoli? What are their functions and what do they look like?

Answer 11

Type I: minimum barrier to gas exchange and so they are squamous or flat in appearance. Type II: They produce and secrete surfactant, so they are cuboidal and between the junctions of 2 alveoli Dust Cells / alveolar macrophages: scavenge for particles that don’t belong in the alveoli - these are usually hanging out in the lumen.

Question 12

What type of tissue is found in the lamina propria?

Answer 12

Lymph

Question 13

What is A, B, C?

What is this layer called?

Answer 13

A: Goblet Cells, which secrete mucus

B: Ciliated pseudostratified epithelial cells

C: basal stem cells

Respiratory Epithelium

Question 14

What is A and what is it’s purpose?

What is D?

What is C and what is found here?

What layer is B and what can be found here?

What is E?

Where is this section from and how do we know?

Answer 14

Hyaline cartilage (which helps keep the airway open)

Respiratory epithelium

Lamina propia: lymph, blood vessels

Submucosa: contains ACH receptors (effect cilial mvmt and frequency), immunologic fx of serous/mucus glands

Adventitia

This is from the trachea because the hyaline cartilage is more ring-like than disc-like.

Question 15

What type of tissue is *?

What tissue is at the arrow?

What part of the airway am I in and how do you know?

Answer 15

hyaline cartilage

smooth muscle

bronchi (most likely secondary), bc the cartilage is in discs, not a ring.

Question 16

What layer is the arrow?

What layer is the pointer?

What is the *?

What is the tissue marked “a”?

What structure is in the green circle?

What type of RE is present here?

Answer 16

Smooth muscle

lamina propia

lumen

discs of cartilage

glands!

columnar epithelium

Question 17

What type of epithelium is found here?

Identify the structure marked by *

What is the structure marked by the pointer?

What is NOT present in this slide that helps us know where we are?

Where is this in the system?

Answer 17

Columnar, with some cuboidal

lamina propia

smooth muscle

no cartilage, no pseudostrat epithelium

So we are in the bronchioles!

Question 18

What are the blue arrows?

What is the green arrow?

What level of the respiratory system is this slide taken from and how do I know?

Answer 18

Ciliated cuboidal epithelial cells

Clara cell

Bronchioles: clara cells, cuboidal cells, a complete absence of cartilage

Question 19

What is the *?

What type of bronchiole is at the arrow head? What is the primary fx?

What type of bronchiole is at the arrow? What is the primary fx?

Answer 19

alveoli

respiratory - respiratory

terminal - last conducting portion

Question 20

What type of cell is at the green arrow?

Blue arrow?

Red arrow?

What type of connective tissue is in alveolar walls and why?

What is in the black arrow and bracket and what does it do?

Answer 20

Type II alveolar cell - surfactant, stem cell

Type I alveolar cell - 90% of the SA of the alveoli, squamous to allow for easy gas exchange

Marcophage - immunity

Elastin, better for expansion and recoil

Port of Kohn, for communication and collateral circulation

Question 21

If this a 58 year old man (a few months apart) with a chronic cough and a 60-70 pack year history admitted with SOB and lab values reading SPO2 88%, ph 7.34, PaCO2 60, HCO3 28, and PaO2 50 what are your conclusions regarding:

1. What do the values indicate?
2. What part of the lungs is affected?
3. What differences might we expect to see between each?
4. What disease is this?
5. What parts of lung fx will be affected?
6. What meds would be appropriate?
7. What observations would we be looking at?

Answer 21

1. He’s hypercapnic and hypoventilating.
2. bronchi
3. lamina propia is thicker, the epithelium has converted to stratified squamous which means there’s no cilia, glands, ducts which means we can’t get much mucus out)
4. chronic bronchitis
5. airway clearance, less things to combat infex, narrowing of the airway effects ventilation
6. bronchodilator, corticosteroid
7. blue bloater (cyanosis), use of accessory muscles to breathe / labored breathing, lots of coughing

8.

Question 22

What pathology is this?

Answer 22

Emphysema

Question 23

1. What lobe is affected?
2. What part of the lungs is affected?
3. How would lung function be effected?
4. What disease is this?
5. What findings do we expect on physical exam?
6. What meds are indicated?
7. What PT interventions would you suggest for this patient?

Answer 23

1. left lower
2. alveoli
3. no gas exchange, no air moving moving at all
4. pneumonia
5. abnormal breath sounds, fremitus (you’ll hear more one side when talking than the other bc the consolidation will resonate).
6. antibiotics, bronchodilators, expectorant
7. Chest PT

Question 24

Name the 3 layers of the heart and vessels.

Answer 24

Tunica intima / endocardium

Tunica media / myocardium

Tunica Adventitia / epicardium

Vessels are on the left / the heart itself is on the right

Question 25

What layer of the heart is the vasa vasorum located and what is its purpose?

Answer 25

It's part of the epicardium and is a collection of blood vessels that supply the heart itself.

Question 26

What are the cells called that make up the conduction system of the heart? What layer are they located in?

Answer 26

Purkinje cells are located in the subendocardial layer.

Question 27

What are 2 ways to ensure synchronous firing of the cardiac muscle cells?

Answer 27

branching and intercalated discs

Question 28

Name the 4 types of arteries, their individual functions, and give some characteristics of each type.

Answer 28

1. Elastic (also called conducting), maintain arterial blood flow - they have a thick tunica media (which allows for many layers of elastin). 2. Muscular (also called distributing) - regional or local distribution depending on size - these have a less thick tunica media than elastin (so, less elastin) but have an IEL and EEL 3. Small/Capillaries: local distribution to capillaries and regulate BP by increasing peripheral resistance (the tunica media is less thick, and there is a much thinner tunica adventitia). 4. Arterioles and Meta-arterioles: these have a bypass mechanism to shunt to the venous system and a very thin tunica media - the difference between the arteriole and the meta-arteriole is the first has a continuous layer of smooth muscle vs. the second is discontinuous.

Question 29

Name some differences between veins and arteries.

Answer 29

veins have: larger and abnormal shaped lumens, thinner walls, less elastin and smooth muscle fibers but have more collagen, some have valves.

Question 30

Name the different types of veins, funx of each, and some characteristics of each.

Answer 30

1. Post capillary venules - these play a role in inflammatory muscles, have more RBC than capillaries and related lymph vessels. 2. Larger "muscular" venules - presence of 1-2 layers of smooth muscle 3. Small veins - 2-3 layers of smooth muscle and well-developed adventitia, have valves. 4. Medium to large veins, more developed tunica intima, less developed tunica media - thickest layer is tunica adventitia.

Question 31

1. Identify A, B, C. Also, what is D? 2. What type of fibers are shown by the green arrows and what is their function? 3. What structure is this?

Answer 31

1. (inner to outer) Endothelium, Subendocardium, Endocardium (the endocardium is made up of the endothelium and the subendocardium) and D is the myocardium or, cardiac muscle. 2. Purkinje fibers, conduction 3. Ventricles of the heart

Question 32

1. Identify the layers of A, B, E, and D. 2. What are the main components of D? 3. What type of vessels are at the tip of the arrows? 4. What is the functional significance of the proximity and the abundance of these structures? 5. What are the structures labelled C?

Answer 32

1. A is the endothelium. B is the subendocardium. This makes E the endocardium. D is the myocardium. 2. Desmosomes, fascia, intercalated discs, gap jx, mitochondria 3. capillaries 4. provision of a constant supply of gasses and nutrition 5. Cardiac muscle cells.

Question 33

1. What are the down arrows? And what is the advantageous of these? 2. What do the pointers point to? And what is their fx?

Answer 33

1. Branching, synchronicity 2. Intercalated discs, differentiation of cells, communication, mechanical stability

Question 34

1. What layers are 1, 2, 3? 2. What is 4 and what is it's purpose? 3. What type of artery is this and how do we know?

Answer 34

1. tunica intima, tunica media, tunica adventitia 2. vaso vasorum, blood supply 3. This is an elastic (or conducting) artery becuase there are MANY elastic layers in the tunica media.

Question 35

1. Identify the layers a, b, c and bracket. 2. What is distinctive about this slide? 3. What is functional significance of this difference? 4. What is at the arrow? 5. What type of artery is this?

Answer 35

1. Tunica media, EEL, tunica adventitia, and the bracket shows tunica intima and IEL. 2. lots of smooth muscle 3. Better distribution of blood. 4. an endothelial cell 5. a distributing or muscular artery

Question 36

1. About how many layers of smooth muscle are there in A vs. B. and what does this tell us about vessel type? What do the appearances tell us about their functional differences?

Answer 36

1. There are 8 layers in A, and only a few in B. The layer sizes are also different even though the layer types are the same. A is a small artery, B is a small vein (remembering that in venules there is no distinct adventitia). A will have a higher capacity to contrict and a higher pressure so will need to be thicker.

Question 37

1. What are A, B, C, and D?

Answer 37

1. A - venule - no adventitia, a larger ovoid lumen with 1 layer of smooth muscle with an discontinuous membrane (because these are almost leaky). B - arteriole - more muscle, more spherical lumen C - capillary - 1 layer thick membrane to allow for only 1 blood cell at a time to allow for better gas exchange. D - small artery - 6-7 layers of smooth muscle.

Question 38

What is A and what is its function? What is B and what its its function?

Answer 38

An endothelial cell which provides a protective barrier, allows for nutrient exchange, and releases secretory substances. A pericyte which is essentially a stem cell for capillaries, smooth muscles, and fibroblasts.

Question 39

What part of the respiratory tract is this? Identify the layers. What type of epithelial cells line this portion?

Answer 39

Trachea Mucosa (C), Submucosa (A), Cartilaginous layer (B), Adventitia (D) Ciliated Pseudostratified Columnar (Respiratory Epithelium)

Question 40

What portion of the respiratory tract is this the upper picture and how can you tell? Howsabout the bottom?

Answer 40

Bronchi - discs of cartilage. Bronchioles - no more cartilage.

Question 41

Identify the layers of the heart wall.

Answer 41

C: Epicardium A: Myocardium B: Endocardium (includes endothelium and subendocardium that contains purkinje fibers when present) \*innermost layer