Histology-Respiratory System Flashcards
What nervous component fall into the respiratory control center?
CNS, Phrenic nerves, Vagus nerves, Sensory nerves, Sympathetic nerves and parasympathetic nerves.
What are the components of the ventilatory pump that create the negative pressure necessary for gas entry?
Chest wall muscles, skeleton and connective tissue. Pleura, airways and spinal cord/peripheral nerves.
You are just sitting, staring out the window, thinking about nothing. What muscles are helping you breath in this state?
Muscles involve in quiet inspiration are the SCM, Scalenes, External Intercostals, Diaphragm, and Transversus abdominis.
What muscles are involved in quiet expiration?
None. The elastic recoil in lungs is what causes the lungs to relax after inspiration.
What muscles are involved in labored breathing?
Forced expiration: abdominal muscles (forces diaphram superiorly), internal intercostals (depress ribs). Forced inspiration: SCM, scalenes and pectoralis minor (all elevate the chest).
How does olfaction occur? What characteristics of olfactory tissue can help you distinguish it from respiratory epithelium?
Olfactory cells span the epithelium with axons going out basally to form the olfactory nerve and cilia spanning the epithelium apically. These cilia are able to bind molecules in the air and send impulses to the brain to communicate what you are smelling. Note that the sustentacular cells support the olfactory cells and that there are no goblet cells.
What is indicated by the #1 and the arrows shown below?
1) note the hyaline cartilage indicative of the nasal septum. The arrows indicate epithelial cells that secrete serous fluid from olfactory glands that aids in warming up the air as it enters and swirls around the turbinate bones.
What part of the tissue seen in this slide is responsible for sensing the particles we breath in the air?
*
Label the different numbers indicated in the slide below.
Note the olfactory axons coming out of the bottom of the epithelium and sending larger nerves back to the CNS.
What structures are indicated in the image below?
*
What is indicated by the arrow below?
This is the transition region in the human nose where olfactory patches change from olfactory epithelium to psuedostratified ciliated columnar respiratory cells. (Note goblet cells in PCC epithelium).
What structures are indicated below?
*
What are the histological differences seen when you are looking at the true and false vocal folds?
True vocal folds have stratified squamous epithelium covering their surface with a skeletal muscle core (vocals muscle). False vocal fold are covered in PCC epithelium with serous glands.
On which vocal folds would you most likely find the cells seen below?
These are mucosal glands that are present on the false vocal folds. Notice glandular cells secreting fluid into ducts.
What different tissue types are found in the trachea?
Smooth muscle (trachealis), hyaline cartilage and sometimes bone.
How does our respiratory tract trap dust in the air and provide a nice, fat loogie for your spitting?
Muco-ciliary escalator. Goblet cells secrete mucus that lines the respiratory tract and traps dust. Cilia on PCC epithelium then sweep the mucus up towards the mouth. Brush cells sense “stuff” that needs to get out and stimulates the cough reflex. Finally small granule cells are the endocrine cells of the respirator epithelium.
What types of cells are found in the epithelium indicated below?
PCC epithelial cells, basal cells and goblet cells.
How does respiratory tissue change as you go deeper into the bronchial tree?
Decreased secretory cells and increased smooth muscle and elastic fibers.
What is the structure indicated below?
It is a bronchus. Note that the bronchus has hyaline cartilage surrounding the lumen.
What are the structures indicated below?
Note the hyaline cartilage and respiratory epithelium surrounding the bronchus. Note the thin endothelial cells lining the lumen of the artery with underlying smooth muscle.
What structures are indicated below?
Note the thin walls, smooth muscle, elastic fibers and small cartilage plates in the bronchus. Also note that none of the alveoli open into the bronchus.
What structures are indicated below?
Note the absence of cartilage in the bronchiole and presence of cartilage in the bronchus. Also note how the epithelium changes as you move from the bronchus (PCC and goblet cells) to the bronchiole (fewer PCC, smooth muscle and Clara cells).
What do the cells indicated in the image below do?
These are Clara cells. They make surfactant and modulate the inflammatory response.
What requirements must be met for the gas exchanger system to be able to exchange gas?
Large area for gas diffusion, short diffusion distance, minimize collapse and match ventilation with blood flow.
What helps you differentiate between pulmonary arteries and pulmonary veins?
The arteries run adjacent to the bronchi. The veins are more separated from the bronchi and in the actual lung parenchyma.
What differences exist between pulmonary arteries and systemic arteries?
Pulmonary arteries have less smooth muscle because they are under lower pressure.
At what point do you start getting air exchange in the lungs?
When the terminal bronchioles (no alveolar openings) become respiratory bronchioles w/alveolar openings.
How does perfusion match ventilation
As PO2 drops in the alveolus (as in hypoxic situations), the resistance to flow in the capillary increases and flow to non-ventilated sections of the lung decreases.
What different layers are found in the tissue sample shown below?
Epithelial layers are on the outside border of the alveoli where it contacts air. Endothelial layers are on the inside of the alveolar capillaries where RBCs are flowing.
What are the different types of cells that make of the layer of the alveolus indicated below?
Type I (flatter and larger) and Type II (produce surfactant) pneumocytes. Alveolar macrophages (dust cells) are also found in the interstitium of this area.
What types of fibers are found in the alveolar spaces?
Reticular fibers and elastic fibers
The cell below is found in the lung alveoli. What type of cell is it? What would its counterpart look like?
It is a type I pneumocyte. Type II pneumocyte is seen below.
Where in the airway is this section most likely taken from?
Note the absence of cartilage, presence of smooth muscle, respiratory epithelium and mucous glands. This indicates that it is probably deeper down in the bronchiole level.
What muscle is indicated by the arrow. What type of muscle is it?
Trachealis. Smooth muscle.
What types of epithelium are found in the section below?
This is the epiglottis, note the large elastic center. Respiratory epithelium is found on the posterior of the epiglottis and stratified squamous epithelium is found on the anterior portion.
