respiratory system

Question 1

what is the primary muscle in resp sys

Answer 1

diaphragm

Question 2

explain inspiration

Answer 2

diaphragm contracts increasing thoracic cavity volume, air goes in

Question 3

explain expiration

Answer 3

diaphragm relaxes, lungs collapse + expels air

Question 4

what are the two classifications of the resp sys

Answer 4

conducting and respiratory zones

Question 5

what is involved in the conducting zone

Answer 5

gaseous transport, filters, humidifies and warms air.
composed of nasal cavity, nasopharynx, larynx, trachea, bronchi, bronchioles

Question 6

what is involved in the respiratory zone

Answer 6

site of gaseous exchange. composed of bronchioles, alveolar ducts, alveolar sacs and alveoli.

Question 7

define olfaction

Answer 7

refers to smell

Question 8

describe the respiratory mucosa

Answer 8

pseudostratified ciliated columnar epithelium with goblet cells.
has lamina propria- loose collagenous layer underlying the resp epi.
mucosal layer is separated by presence of a submucosa

Question 9

describe the nasal cavity structure

Answer 9

divided into two nasal cavities which is separated by a nasal septum (cartilage). these cavities and the paranasal sinuses are lined by resp mucosa
bones called turbinate bones project into the nasal cavities.

Question 10

what does the lamina propria of nasal mucosa contain

Answer 10

serous and mucous glands

Question 11

nasopharynx

Answer 11

space above soft palate at back of the nose. this connects the nose to the mouth. consists of pseudo. ciliated columnar epi. serous and mucous glands in lamina prop

Question 12

General structure of trachea

Answer 12

flexible tube of fibroelastic cartilage. has a series of c shaped rings of hyaline cartilage that supports the tracheal mucosa, which prevents the trachea from collapsing during inspiration.
smooth muscle - trachealis muscle joins the free ends of the rings posteriorly. longitudinal muscle can be found behind the trachealis muscle.

Question 13

describe the respiratory epithelium of the trachea

Answer 13

epithelium is similar to rest of the RS.
variety oc cells found include:
- pseudostratified columnar cells with cilia
- goblet cells and basal cells (upper trachea)
- serous cells and stem cells (lower trachea)

beneath the basement membrane: lamina propria and submucosa (mixed seromucinous glands).

Question 14

describe the structure of primary bronchi

Answer 14

respiratory epi = shorter than trachea with fewer goblet cells
lamina propria= more dense with large quantity of elastin

LP separates from submucosa by smooth muscle, which has less seromucinous glands

has a cartilage framework which is arranged into flattened plates rather than rings.

Question 15

describe the primary bronchi resp epithelium

Answer 15

pseudostratified, with some ciliated cells.
have goblet cells, and LP has elastin and mast cells.

Question 16

describe tertiary bronchi

Answer 16

tall and columnar, goblet cells diminished in number.
LP is thin and encircled by smooth muscle which permits contraction of the bronchi.
submucosa has sparse seromucinous glands
cartilage framework reduced to a few irregular plates.
small aggregations of lymphoid tissue

Question 17

describe structure of bronchioles

Answer 17

no cartilage support, no submucosal glands. ciliated columnar cells, few goblet cells, clara cells.
smooth muscle layer found in bundles in various orientations

Question 18

describe terminal and respiratory bronchioles

Answer 18

terminal: smallest passages of CZ. each branches into respiratory branches (bronchioles)

respiratory bronchioles
- ciliated cuboidal cells
- no goblet cells
- clara cells: produce surfactant, act as reserve cells (stem cells) and contain enzymes for detoxification
- each gives rise to alveolar duct + sac

Question 19

describe alveolar wall

Answer 19

epithelium
type 1 pneumocytes: large squamous cells, alveolar lining, part of gaseous diffusion barrier
type 2 pneuomocytes: round cells which secrete surfactant, capable of division

supporting tissue
fine reticular, collagenous and elastic fibres with some fibroblasts.

blood vessels
capillaries