Respiratory System Terms and Concepts (exam 2)

according to Boyles Law: if you ____ volume you ____ pressure

increase, decrease

a decrease in pressure causes

air to enter lungs

boyles law

pressure varies inversely with volume for a given gas

diaphragm shape in 2 stages

• dome when resting

• flat when active

when the thorax expands transversely

the thoracic cavity increases in volume

when the thorax expands vertically

the thoracic volume increases

5 types of vertebrae in spine

HINT: CTLSC

• cervical x7

• thoracic x12

• lumbar x5

• sacrum x5

• coccyx x4

rib breakdown

• true ribs 1-7

• false ribs 8-10

• floating ribs 11-12

thorax includes:

thoracic vertebrae, ribs, sternum

thorax function

protect and support respiratory function

support allows for

places of attachment

sternum function

attachment for the muscles and cartilage of the thorax

sternum anatomy

1. manubrium

2. body

3. xiphoid process

costal cartilage connects

ribs to sternum

pulmonary system

• larynx

• trachea

• bronchi

• alveoli

• lungs

visceral pleura

inner membrane directly covering the kings

parietal pleura

other layer lining chest wall and diaphragm

intrpleural pressure is

negative

ventilation is

the physical process of moving air in and out of the lungs

key structures involved in ventilation

• ribcage

• lungs

• diaphragm

• intercostal muscles

increase in the volume of container leads to

decrease in gas pressure

decrease in the volume of a container leads to

increase in gas pressure

gases move from areas of high pressure to

areas of low pressure

during inspiration

• external intercostal muscles contract

• internal intercostals relax

• diaphragm contracts and flattens

• rib cages moves up and out

volume changes during inspiration

• volume of thoracic cavity increases

• volumes of lungs increase

• pressure in lungs decrease

during expiration

• external intercostal muscles relax

• internal intercostal muscles relax

• diaphragm relaxes and moves up

• rib cage moves down and in

volume changes during expiration

• volume of thoracic cavity decreases

• volume of lungs decrease

• Pressure in lungs decrease

muscles of inspiration

• diaphragm (unpaired)

• scalenes

• sternocloildmasteiod

• external intercostals

• interchondral part of internal intercostals

equilibrium (stage in between insp/exp)

35-40% vital capacity

high lung volume → above 55% VC

• lungs and chest wall will recoil to smaller sizes

• combined recoil forces contribute to high alveolar pressure

lung volume at equilibrium → 38% VC

• chest wall will expand and is equal and opposite to the tendency of the lungs to collapse

lung volumes that are above 38 VC and less than 55 VC

• relaxation pressure is positive meaning that air contained in the lungs has a higher pressure than the atmosphere

• to inspire at this volume active forces must be generated

low lung volumes → below 38%

• air in lungs has a lower pressure than the atmosphere

• inspiration is passive and expiration is active

KENT CURVE VOLUMES

• lung volume at equilibrium → 38% VC

• high lung volume → above 55% VC

• lung volumes that are above 38 VC and less than 55 VC

• low lung volumes → below 38%

pressure is

forces per unit area

molecules move and ____ into one another and

the walls of the container that they are in

gas pressure

the sum of forces of collision divided by the area of container walls

pressure differential

change in pressure across containers

what are the different types of pressures within the respiratory system

• alveolar (lungs)

• pleural

• abdominal

Boyles law says that volume is inversely proportional to pressure so:

• increase pressure by compressing gas into smaller volume

• decrease pressure by increasing container volume

air flow is

volume (L), change (sec) = airflow

gas flows from regions of high pressure

to regions of low pressure

airflow is proportional to pressure differential, so:

increase in pressure = increase in airflow

during inspiration lung pressure _____ atmospheric pressure

lessens

during expiration lung pressure _____ atmospheric pressure

increases

how can lung volume be measured

all lung volumes are measured directly except

residual lung volume

all capacities are a combination of ______

2 or more volumes

types of lung volumes

• tidal

• inspiratory reserve volume

• expiratory reserve volume residual volume

tidal volume

volume of air exchanged during resting breathing

inspiratory reserve volume

maximum volume of air that can be inspired after a tidal inspiration

expiratory reserve volume

maximum volume of air which can be expired after a tidal expiration

residual volume

amount of air left in the lungs after a maximum expiration

how many volumes make up a capacity

2

total lung capacity

total amount of air that can be held in the lungs (all volumes added together)

• tidal volume + inspiratory reserve volume + expiratory reserve volume + residual volume = total lung capacity

inspiratory capacity

maximum volume of air that can be inspired after a tidal expiration

• tidal volume + respiratory reserve volume = inspiratory capacity

vital capacity

maximum amount of air that can be inspired after a maximal expiration

• tidal volume + inspiratory reserve volume + expiratory reserve volume = vital capacity

functional residual capacity

amount of air in lungs after tidal expiration

• expiratory reserve volume + residual volume = functional residual capacity

what are the 2 ways that the lungs are expanded or contracted

• recoil of the lung-thorax unit (passive)

• muscle force (active)

inspiration is always caused by ____ muscle forces

active

expiration is ____ during rest breathing

passive

there is a mix of active and passive forces during _____

speech

the lungs and thorax are elastic which means

they resist being deformed by rest

the lung-thorax unit will exert a force to return to rest called _____

elastic recoil force

recoil pressures

pressures within the lungs and are a source of power for the speech system

what’s the difference between residual volume and dead air

residual volume is the air remaining in the lungs after the maximum possible exhalation and dead air is in the conducting airways and will never participate in the gas exchange