1 Anatomy and Physiology Flashcards
what is the pathway of air
mouth/nose
trachea
bronchi
bronchioles
alveoli
what factors assist the alveoli in gaseous exchange
large SA -> large area for diffusion
one cell thick walls -> small diffusion distance
lots of capillaries -> maintains concentration gradient
moist walls -> helps diffusion as gases dissolve
large blood supply -> large concentration gradient
how do RBC carry oxygen
Oxygen combines with haemoglobin in the red blood cells to form oxyhaemoglobin
can RBCs carry CO2
yes haemoglobin also can carry CO2
structure and job of arteries
job:
carry blood away from the heart at high pressure
carry oxygenated blood (except for the pulmonary artery)
blood flows through at fast speeds
structure:
thick elastic muscular walls to withstand the high pressured blood (as its coming straight from the heart) and to maintain the high blood pressure as it recoils after the blood has passed through
narrow lumen -> helps maintain high pressure
structure and job of capillaries
job:
carry blood at low pressure within tissues
carries both oxygenated and deoxygenated blood
blood flows through at slow speeds
structure:
one cell thick
one cell thick walls -> allows substances to easily diffuse in and out
‘leaky’ walls -> allow blood plasma to leak out and form tissue fluid surrounding cells
structure and job of veins
job:
carries blood at low pressure towards the heart
carries deoxygenated blood (except the pulmonary vein)
blood flows at low speeds
structure:
thin elastic walls
large lumen -> reduces resistance to allow the low pressure blood to flow
contains valves -> to prevent backflow as the blood is a low pressure
whats the lumen
the empty space inside blood vessels
what blood vessel goes into the heart from the body
vena cava - vein - deoxygenated
what blood vessel goes from the right ventricle to the lungs
pulmonary artery - deoxygenated
what blood vessel goes from the lungs into the left atrium
pulmonary vein - oxygenated
what blood vessel goes from the left ventricle to the body
aorta - artery - oxygenated
journey of blood through the heart
vena cava
right atrium
tricuspid valve
right ventricle
pulmonary artery
lungs - gas exchange occurs
pulmonary vein
left atrium
bicuspid valve
left ventricle
aorta -> body
blood is deoxygenated until reaches the lungs
what is the cardiac output
the volume of blood that is pumped by the heart (the left and right ventricle) per unit of time
what is the stroke volume
the volume of blood pumped out of the left ventricle during one cardiac cycle
what is the heart rate
the number of times a heart beats per minute
equation linking heart rate, stroke volume, cardiac output
Cardiac output(Q) (cm3min-1) = heart rate (bpm) x stroke volume (cm3)
what is an anticipatory rise
a small rise in heart rate just before exercise occurs
the brain releases a small amount of adrenaline which causes the heart rate to increase and therefore better handle the demands of the physical activity
how do valves work
open due to pressure and close to prevent backflow
what is the order of the cardiac cycle
atrial and ventricular diastole (chambers relax and are filled with blood)
atrial systole (atria contract and push remaining blood into the ventricles)
ventricular systole (ventricles contract and push blood into out through the aorta and pulmonary artery)
what is systolic
when the heart contracts
what is diastolic
when the heart relaxes
what is the cardiac cycle
the pattern of contraction and relaxation of the hear during one complete heartbeat
what is the tidal volume
the amount of air breathed in with each normal breath
what is the expiratory reserve volume
the maximum amount of additional air that can be forced out of the lungs after a normal breath
what is the inspiratory reserve volume
the maximum amount of additional air that can be taken into the lungs after a normal breath
what is the residual volume
is the amount of air left in the lungs after a maximal out breath. This air helps to keep the lungs partially inflated to protect the microscopic structures from being damaged
what causes inhalation and exhalation
change in air pressure
process of inhalation (inspiration)
rib cage expands as intercostal muscles contract
diaphragm contracts and moves down which causes the air pressure to decrease which pulls air in
process of exhalation
rib cage gets smaller as intercostal muscles relax
diaphragm relaxes and moves up which causes air pressure to increase which forces air out
which muscles aid breathing during exercise
pectorals, sternocleidomastoid, abdominals
how does the pectorals and sternocleidomastoid aid in breathing during exercise
help during inhalation by lifting the ribs up and out even more
how do the abdominals aid in breathing during exercise
help during exhalation by pulling the ribs back in even further
what does EPOC stand for
exercise post oxygen consumption
how does EPOC occur
caused by anaerobic exercise (which produces lactic acid) and requires the performer to maintain increased breathing rate after exercise to repay the debt (remove lactic acid produced)
what is redistribution
cardiovascular system redistributes blood so that more of it goes to the working muscles and less of it goes to other organs (such as the digestive system)