structure of airways from trachea to alveoli

Question 1

function of the cartilage

Answer 1

support - very strong tissue = prevents collapse of trachea and bronchi
flexible = trachea can bend to allow oesophagus to expand behind for digestion

Question 2

function of goblet cells

Answer 2

cleaning - secrete mucus containing glycogen (protein with carbohydrate chain that sticks out). Mucus traps dust, pathogens, and pollen

Question 3

function of the ciliated cells

Answer 3

cleaning - hairlike projections = beat in synchronised pattern to waft mucus to back of throat (pharynx)

Question 4

function of smooth muscle

Answer 4

adjusting diameter - contracts to constrict and narrow airway if there is a harmful substance in air
relaxed to dilate = widen airway which allows airflow to alveoli

Question 5

function of elastic fibres

Answer 5

adjusting diameter - alveoli stretch (not EXPAND) on inhalation + recoil on exhalation to expel air.
bronchiole = smooth muscle contracts, elastic fibres stretch, when SM relaxes, elastic fibres recoil

Question 6

function of squamous epithelium

Answer 6

exchange - thin flattened cells - they enable short diffusion distance, increasing rate of gaseous exchange.