RESPIRATORY SYSTEM Flashcards
what are the functions of the respiratory system? (7)
(1) air is moved to and away from respiratory surfaces
(2) ensures cells receive an adequate and consistent supply of O2
(3) excrete CO2 (product of cellular metabolism)
(4) protection from dehydration, temperature changes, and micro-organism invasions
(5) producing sounds used for speaking
(6) enabling sense of smell
(7) working with other physiological systems, maintaining homeostasis
what is the trachea and its role?
a cylindric tube located in the neck which is in contact with the oesophagus. its role to convey air into the lungs
what is the trachea composed of?
the trachea is composed of c-shaped cartilages, membrane, and trachealis muscle
what does the trachea divide into?
the trachea divides into two bronchi
what is the approximate length and width of the trachea?
11cm in length
2cm in width
what are the three main layers of the trachea?
(1) mucosa
(2) submucosa
(3) adventitia
what is the adventitia composed of?
c-shaped rings of cartilage, more specifically, connective tissue with elastic and collagenous fibres
what is the mucosa composed of?
mucosa is composed of goblet cells and ciliated epithelium
what are goblet cells?
they are specialised epithelial cells which secrete mucus, serving as the primary site for mucosal absorption and nutrient digestion
what is the role of mucosa?
to protect underlying structures, secretes mucus, and absorbs water, salts, and various other solutes
what is submucosa?
a connective tissue deep within the mucosa
what are the four structures of the upper airways?
(1) nose
(2) pharynx
(3) larynx
(4) trachea
what are the three structures of the lower airways?
(1) primary bronchi
(2) bronchioles
(3) alveoli
what are the primary bronchi?
branching off the trachea, the left and right bronchus joining to the lungs
what is the structure of the primary bronchi?
it is composed of rings of hyaline cartilage, fibrous tissue, mucous membrane, and glands
what is the role of the primary bronchi?
to convey air to the lungs
what does the primary bronchi divide into?
secondary bronchi, then tertiary bronchi
what does the left primary bronchus divide into?
it divides into bronchi for the superior and anterior lobes of the lungs
which side of the primary bronchi have a more direct passage to the lungs?
the right side, as it is wider, shorter, and straighter
