internal transport

1.divided into 4 chambers 2.two upper chambers called atria, receive blood from lungs or body and transport it to the ventricles 3.two lower chambers called ventricles, pump blood out of the heart and all around the body 4.chambers on the left hand side and right hand side are completely separated by septum

1.left atrium receives blood from the pulmonary vein, which carries blood from the lungs 2.blood flows to the left ventricle through the bicuspid valve 3.the blood in the left ventricle is pumped into the aorta, which takes the blood around the body

1.the right atrium receives blood from the rest of the body, arriving through the vena cava 2.blood flows to the right ventricle through the tricuspid valve 3.the right ventricle pumps blood into the pulmonary artery which carries it to the lungs

1.heart rate increases so more blood reaches the muscles, more aerobic respiration and energy release, removal of excess co2 and lactic acid 2.during exercise muscles respire more releasing more carbon dioxide which dissolves in the plasma lowering the ph 3.chemoreceptors in cartoid artery and the aorta detect the acidic ph and send impulses to cardiovascular center in the brain medulla which sends impulse to pacemaker of the heart to increase the heart rat3

fats and glycerol build up in atheroma on walls of coronary artery blocking them, less blood reaches the heart muscle cells, so less o2, and glucose, less aerobic respiration resulting in cell death causing heart attack

1.smoking 2.diet 3.stress 4.lack of exercise

1.stents 2.heart transplant 3.artificial heart 4.statins 5.plant stanol esters 6.beta blockers

widen the narrowed or blocked coronary artery, allowing blood to flow through them

surgical transplant performed on patients with severe heart failure

lifesaving

1.few donors available 2.long recovery time 3.expensive

synthetic device made of plastic and some metal alloys, their purpose is to keep people alive while waiting for suitable donor

chemicals that lower blood cholesterol, they inhibit an enzyme that is involved in the synthesis of cholesterol

lowers blood cholesterol levels

class of drugs, used to protect against second heart attack, they block receptors of adrenaline in various parts

genetic factors high salt content lack of exercise obesity smoking kidney disease

1.very strong walls to withstand high pressure 2.have elastic tissue in their walls that can stretch and recoil 3.narrow lumen to maintain high pressure 4.walls of the arteries have muscles that control size of lumen

1.lumen is wider in vein than in arteries to decreases resistance to blood flow 2.have valves in them to stop the blood flowing backwards 3.thin walls to be easily squeezed by skeletal muscles

thin walls for short diffusion distance wall has pores for rapid exchange

1.allows transport of o2, glucose, amino acids, minerals, vitamins from blood to cells 2.allows co2 and urea out of cells to blood

yellow part of the blood

transports water, dissolved nutrients, wastes, hormones, and co2

transports oxygen

biconcave to increase surface area to increase rate of diffusion no nucleus to provide more space for haemoglobin