Anatomy - Cardiovascular & Respiratory Histology Flashcards
what does the lungs normally look like on histology?
honeycomb like structure to increase surface for gas exchange
what is the conducting portion of the respiratory system?
nasal cavities to terminal bronchioles
what is the respiratory portion of the respiratory system?
respiratory bronchioles to alveoli
what is the conduction portion?
a series of interconnected cavities and tubes
help to filter, clean air and warm it
what allows the gas exchange?
vast network of capillaries
what are the nasal cavities down to the bronchi lined with?
respiratory epithelium
what is the respiratory epithelium?
ciliated pseudo stratified (loots like lots of layers but they all actually touch the BM) columnar epithelium with goblet cells
what is the function of goblet cells?
secrete mucus that lines the surface and is sticky that traps any inhaled dust or debris
what Is the function of the cilia in the respiratory tract?
moves the trapped particles caught in the mucus up towards the pharynx out of the respiratory system
wha typically happens to someone who smokes?
they have reduced cilia
what supports the trachea?
10-12 C shaped hyaline cartilages
help to maintain an open airway
where are the chondrocytes located?
cartilage cells embedded in the C shaped cartilage that surrounds the trachea
what joins the 2 ends of the C shaped cartilage in the trachea?
smooth muscle (trachealis muscle)
why is the trachealis muscle important?
allows for change in diameter of the trachea
important for coughing
can change shape rapidly
what kind of epithelium is the trachea lined with?
stratifciliated pseudo stratified columnar
what is in the submucosa of the trachea?
seromucous glands
adds to the sticky layer to catch any dust or debris
which layers together form the mucosa?
the epithelium and the lamina propria
what are seromucous glands?
produce watery and mucus secretions which are delivered to the luminal surface by ducts
what is the structure of the brocnhi?
-irregular plates of cartilage that help to hold the airways open
-these decrease in frequency and size as we move down the trachea
what happens as we move down the bronchi?
less need for mucous secretion and therefor less submucosal glands and goblet cells
what is the structure of the bronchioles?
lose the cartilage
no submucosal glands
smooth muscle makes up most of the wall and keeps the bronchi open
narrower and smaller airways which can be blocked easily so we don’t want much mucous
what type of epithelium are larger bronchioles lined with?
simple ciliated columnar epithelium (not pseudostratified) which has few goblet cells
what happens to the epithelium as the bronchioles decrease in size?
epithelium becomes simple cuboidal with few ciliated cells and increasing number of club cells (Clara cells)
what are club cells (Clara cells)
small cuboidal shaped cells which are found in the bronchioles which have a protective function and secrete antimicrobial and anti-inflammatory immune regulating proteins and participate in the biotransformation of many of the harmful and toxic compounds introduced to the lungs with inhaled air