Respiratory Anatomy Flashcards

Question

Describe the bronchiole wall

Answer 1

Simple ciliated columnar epithelium and club cells lined with watery secretion Smooth muscle Alveolus

Answer 2

Controls air flow by constriction and relaxation

Answer 3

Over-constriction of smooth muscle in the bronchi and bronchioles restricting air flow and requiring bronchodilators to relax

Answer 4

Keep bronchi open - cartilage plates are not prone to collapse Bronchi more rigid than bronchioles because of presence of cartilage plates

Answer 5

Found between epithelial cells in bronchiole walls and secrete a non-mucus watery secretion to keep cells hydrated and air moist

Answer 6

Found between epithelial cells in bronchus walls and secrete mucus

Answer 7

``` Red blood cells (in pulmonary capillary) Endothelial cells (in pulmonary capillary) Squamous pneumocytes (type I cells) Alveolar macrophages Surfactant cells (type II cells) ```

Answer 8

Liquid lining reduces the work of breathing by reducing surface tension in alveoli and stopping alveoli completely collapsing

Answer 9

To secrete surfactant

Answer 10

Very thin trails of cytoplasm in each cell surrounding an area of an alveoli which minimises diffusion distance for gas exchange

Answer 11

Act as normal macrophages to engulf pathogens and foreign particles Last line of defence if air is contaminated

Answer 12

Squamous pneumocyte adjacent to alveolar air space Capillary endothelium adjacent to blood plasma Basement membranes of squamous pneumocytes and capillary endothelium fused to reduce diffusion distance

Answer 13

Right and left main stem bronchi supplying each lung

Answer 14

Lobar bronchi supplying lobes (3 on the right and 2 on the left)

Answer 15

Segmental bronchi supplying segments of the lung (10 on the right and 8 on the left) Each segment has its own air and blood supply

Answer 16

Smooth double layered membrane that covers each lung and lines the thoracic cavity Two pleurae are continuous at the root of the lung (hilum) Separated by thin film of fluid that allows pleurae to slide past each other without friction Fluid also prevents complete separation of the pleurae

Answer 17

Ribcage movement responsible for 25% air movement into and out of the lungs Active inspiration requires contraction of external intercostal muscles which run obliquely between ribs Passive expiration doesn't require muscular action. The ribcage relaxes back to its resting position During exercise, both sets of intercostal muscles become active and both inspiration and expiration require muscular action

Answer 18

Ribs pivot around their joints with the vertebral column. Contraction of the external intercostal muscles lifts the ribs and rotates them around their pivot points. The ribs lift and swing upwards and outwards, increasing the volume of the thorax and allowing air in. The internal intercostal muscles run at right angles to the external intercostal muscles and when they contract they drag the ribs downwards - only for forceful exhalation.

Answer 19

Diaphragmatic muscle contracts which flattens the diaphragm and pulls the central dome down, increasing the volume of the thorax and causing inspiration. Passive relaxation of the muscle lifts the diaphragm back up towards the thorax reducing the volume and causing expiration. Responsible for 75% of bulk flow of air during quiet breathing.

Answer 20

The diaphragm is a dome shaped platform that forms the floor of the thorax and the roof of the abdomen. Its central part is a thin sheet of connective tissue (aponeurosis) called the central tendon. The lateral margins are fast acting skeletal muscle innervated by the phrenic nerve.