GCSE PE: 1B Applied anatomy and physiology

Where does air travel during respiration

nose, trachea, bronchi, bronchioles, alveoli, blood stream

gaseous exchange

-diffusion -oxygen><alveoli

factors of gaseous exchange

-large number of small alveoli -large surface area -short diffusion pathway -large network of capillaries surrounding alveoli

inspiration definition

inhalation of air occurring when we breathe in

expiration definition

exhalation of air occurring when we breathe out

Inspiration process

breathing muscles contract, diaphragm flattens out to make space, intercostal muscles contract causing ribs to rise, air is drawn into lungs

expiration process

Breathing muscles relax, diaphragm curves and returns to original dome shape, weight of the ribs causes them to drop

reduces size of chest cavity, breathe out

Tidal volume

The amount of air that enters the lungs during normal inspiration at rest

Inspiratory reserve volume

The amount of extra air inspired (above that of the tidal volume) during a deep breath

expiratory reserve volume

The amount of extra air expired (above that of tidal volume) during a forceful breath out

residual volume

The amount of air left in the lungs following maximal expiration ( there is always some air left in the lungs following expiration)

arteries

carry blood away from the heart, thick, strong, elastic, highest, pressure, narrow lumen, oxygenated except PA

vein

carry blood towards the heart, thin walls, wide lumen, valves, low pressure, de-oxygenated except PV

capillaries

very thin walls, very narrow lumen, low pressure, usually oxygenated but both, diffusion

vasoconstriction

Process of small arteries that contract to DECREASE their diameter, reducing the blood flow through that particular artery

vasodilation

Process of small arteries that contract to INCREASE their diameter increasing the blood flow through that particular artery to the tissues, occurs during exercise

diastole

filling of heart chambers with blood

systole

emptying of heart chambers

cardiac output

amount of blood pumped per minute

CO factors

heart rate and stroke volume

heart rate

number of times heart beats per minute

stroke volume

amount of blood that leaves the heart per beat

CO formula

Heart rate X Stroke volume

anticipatory rise

cardiac output + heart rate increases shortly before exercise because of expectation of exercise, caused by hormone adrenaline