The Respiratory System

Slide A143 x400 Olfactory Mucosa Technique: H&E Compare with respiratory epithelium. In this section of olfactory mucosa in the nasal cavity note: _ The narrow duct of a serous gland(of Bowman) passing through the epithelium _ The indistinct basement membrane of the epithelium; _ The row of small darkly-staining nuclei of the basal cells; _3-4 rows of pale-stained nuclei of bipolar neurones; _The oval nuclei of columnar supporting(sustentacular)cells; _The remnants of olfactory cilia on the free surface;and _Several large venous sinuses in the lamina propria. What is the function of the Secretion of the serous glands (Bowman)? Continued on next slide

The Respiratory System.

Slide A 144 x400 Respiratory Mucosa Technique:H&E

Compare with Olfactory mucosa. In this section of respiratory mucosa in the nasal cavity note: -The pseudostratified ciliated columnar epithelium with numerous goblet cells -The thick basement membrane ; -The large venous sinuses in the connective tissue below the epithelium; and The eosinophilic spicule of bone. What is the function of large Venous sinuses in the nasal cavity? What is “mucoperiosteum”? What type of bone is demonstrated in this field?

The Respiratory System.

Slide CB32 x100 The Trachea Technique: H&E

Compare with epithelia of intrapulmonary bronchus and bronchioles. In this section of trachea note: -The respiratory epithelium; -The prominent basement membrane; -The underlying vascularised lamina propria; -The numerous muco- serous glands and cartilage. What type of cartilage is this? What is mucoperichondrium?

The Respiratory System. Slide CB 32 x400 The Trachea Technique: H&E

Respiratory epithelium Thick basement membrane. Underlying Vascularised Lamina propria.

The Respiratory System.

Slide CB 97 x100 The Intrapulmonary Bronchus Technique: H&E

In this section of intra-pulmonary bronchus note: -The respiratory epithelium on the prominent basement membrane. -The bundles of smooth muscle in the lamina propria and -The mixed muco-serous glands in the submucosa - The underlying plates of cartilage. How does the structure of the Intra pulmonary bronchus differ from that of the trachea? What is the function of the smooth muscle?

The Respiratory System

Slide B306 x400 The Visceral Pleura Technique: H&E

In this section of Lung note: The simple Squamous epithelium On the free surface. Does a Mesothelium occur ? What does the presence of a Mesothelium tell you about the development of the lung? What is the function of the pleura?

The Respiratory System

Slide A157 x100 Elastic Tissue in the Lung Technique: Elastin Stain

Only elastic tissue has been stained in this Section; Note the blue/ black –stained fibres in The visceral Pleura; The walls of the blood vessels; The walls of the alveolar ducts ;and The interalveolar septa. What is the function of elastic tissue In the lungs?

The Respiratory system Slide A149 x100 Terminal Bronchiole Technique: H&E

In this section of lung note: -The highly folded mucosa of a terminal bronchiole in transverse section. -The ring of eosinophilic smooth muscle; -The accompanying branch of the pulmonary artery;and -The surrounding lung tissue. Identify the epithelium of the Terminal bronchiole. What are Clara cells? Where are they found and What is Their function?

The Respiratory System Slide B305 x100 Respiratory Unit Technique: H&E

In this section through the lung note: -Terminal bronchiole lined by simple columnar epithelium ,which leads into --Respiratory bronchiole lined by simple cuboidal epithelium --Alveolar duct --Alveoli --Macrophages in the connective tissue(which has taken up the black carbon dye.) -Artery which bifurcates

-What is the function of macrophages in the lung?

The Respiratory System

Slide D168 x100 The Alveolar Duct Technique : H&E

In this section through the lung note: -The Alveolar Duct in the centre of the field ; -The numerous alveoli leading from the alveolar duct ;and --The small “ knobs” of smooth muscle at the entrance to the alveoli. What is the function of the “knobs”of the smooth muscle at the entrances to the alveoli?

The Respiratory System.

Slide 98 x100 Alveolar Duct Technique: H&E

In this section through the respiratory portion of the lung Note: -The thin fibro-elastic connective tissue making up the wall of the duct. -The Knob-like thickenings (with smooth muscle) at the entrance of the alveoli sacs into the duct. -Alveoli sacs leading from the duct. What Type of epithelium lines the alveolar duct & alveoli?

The Respiratory System

Slide A152 x1000 The Interalveolar Septa Technique:H&E The small “knobs” of smooth muscle at the enrtance to the alveoli

The Resiratory System.

Slide A152 x1000 Interalveolar Septa in the Lungs Technique : H&E

Note: -The capillaries in the interaveolar septa identified by the eosinophilic red blood corpuscles in single file. -The relatively few flattened nuclei Of the simple squamous epithelial Cells lining the alveoli (TypeI pneumocytes). The more rounded nuclei of the Type II Pneumocytes in the angles between adjacent alveoli. The alveolar macrophages. How do the interalveolar septa arise during the development of the lung and what is their Function? What is the function of the TypeII pneumocyte cells? How did you identify the alveolar Macrophages?What is their function?

The Resiratory System

Slide A152 x1000 Interalveolar Septa In the Lungs 2 Technique: H&E

Eosinophilic red blood corpuscles,Type I pneumocytes,Type II pneumocytes & Macrophages.

The Respiratory System

Slide A152 x1000 Interalveola Septa in the Lungs Technique:H&E

Eosinophilic red blood corpuscles,MacrophagesType I + Type II pneumocytes

The Respiratory System

Slide 98 x400 Knob at entrance to alveolar sac Technique: H&E

In this section see the knob like structure found at the entrance to the alveolar sac

The Respiratory System

Slide 98 x1000 Knobs of Alveolar Duct & Sac Technique: H&E

Images of 2 Knobs found at the entrance to two alveolar sacs.