B4 science Flashcards
Common features of transport systems:
they are made up of tubes or ‘vessels’ that carry materials from one part of the organism to another
they make close contact with cells, such as those of exchange surfaces
Other substances transported in the blood include:
antibodies
hormones
right ventricle function
pumps blood around the rest of the body
left ventricle function
pumps blood around the rest of the body
pacemaker (in the right atrium) function
controls the natural resting heart rate. artifical electrical pacemakers can be fitted to correct irregularities
coronary arteries function
carry oxygenated blood to the cardiac muscle
heart valves
prevent blood in the heart from flowing in the wrong direction
trachea
carries air to/from the lungs. rings of catilage protect the airway
bronchioles
carries air to/from the air sacs (alveoli). splits into multiple pathways to reach all the air sacs
alveoli
site of gas exchange in the lungs. maximises surface area foe efficient gas exchange
capillaries
allows gas exchange between into/out of blood. oxygen diffuses into the blood and carbon dioxide diffuses out
blood
blood is a tissue consisting of plasma, in which blood cells and platlets are suspended
plasma 55% of blood
pale yellow fluid. transports co2, hormones and waste.
red blood cells 45% of blood
carries oxygen. large surface area, no nucleus, full of haemoglobin
white blood cells 1% of blood
parts of the immune system. some produce anti bodies, others surround and engulf pathogens
platlets 1% of blood
fragments of cells. clump together to form blood clots
platlets 1% of blood
fragments of cells. clump together to form blood clots
artery
carry blood away from the heart. thick muscular walls, small lumen, carry blood under high pressure, carry oxygenated blood (except for the pulmonary artery)
vein
carry blood to the heart. thin walls, large lumen ,carry blood under low pressure, have valves to stop flow in the wrong direction, carry de oxygenated blood (exept for the pulmonary vein).
capillary
connects arteries and veins. one cell thick to allow diffusion, carry blood under very low pressure.
lung and gas exchange
the heart pumps low oxygen/high carbon dioxide blood to the lungs
coronary heart disease cause
a build up for fatty substances in the coronary arteries (artherosclerosis)
coronary heart disease effect
oxygen-ated blood cannot get to the cardiac muscle
coronary heart disease treatment
stents: inserted into the blocked artery to open it up. statins: lower harmful cholesterol