PE - heart and blood vessels Flashcards
(24 cards)
arteries
- contains high concentration of oxygen
- carries oxygenated blood away from heart
- high pressure
- thick, muscular walls that adjust their diameter to increase / decrease blood flow
- small lumen
vasoconstriction
contract or make smaller to decrease blood flow
vasodilation
increase diameter and increase blood flow
vein
- carry dark red deoxygenated blood towards the heart
- contain low concentration of oxygen
- no pulse
- thin walls
- large lumen
- have valves so there is no backflow
capillaries
- microscopic blood vessels
- huge network of vessels, linking arteries and veins
- very narrow (1 cell thick)
- allow gaseous exchange, nutrients and waste to rapidly diffuse
pathway of blood - heart
vena cava => right atrium => right ventricle => pulmonary artery => lungs => left atrium => left ventricle => aorta => rest of the body
heart rate
- number of times the heart beats per min (bpm)
stroke vol
- vol of blood pumped with each contraction / per beat
cardiac output
- total amount of blood pumped by the heart per minute
- heart rate x stroke vol
importance of cardiac output / reasoning
- muscles need more oxygen and nutrients, so the heart works harder
- over time, the heart becomes stronger and more efficient
effect of exercise on the heart (during exercise) - cardiac output
- heart rate increases
- stroke vol increases (more blood per min)
- CO increases (to deliver more oxygen to muscles)
effect of exercise on the heart (after long-term training) - cardiac output
- resting heart rate decreases (heart is more efficient)
- stroke vol increases at rest and during exercise
- cardiac output becomes more efficient overall
diastole
- phase of the heart beat
- chambers relax allowing heart to fill with blood
valves
ensuring one-way flow
- stop back flow
systole
- phase of heart beat
- chambers contract and heart ejects all blood
atriums
- upper chambers
- receive blood
ventricle
- lower chambers
- pump blood out
right side
- takes deoxygenated blood from the veins
- delivers to the lungs for oxygenation
left side
- oxygenated blood returns to the heart to the left side
- pumped around the body transporting and delivering oxygen and nutrients.
plasma
- carries nutrients (eg. glu), hormones, and waste products (eg. CO2)
red blood cells
- contain haemoglobin to carry oxygen and CO2
white blood cells
fights infection and are part of immune system
platelets
helps clot the blood and prevent bleeding
haemoglobin
- found in RBC
- bind to oxygen in the lungs to create oxyhaemoglobin
- releases oxygen to muscles during exercise
- carries some carbon dioxide back to the lungs
