Structure/function of circulatory system Flashcards
function of circularity system=
main transport sytem in body. responsible for 02 delivery, nutrients,hormones,medication taken to different parts of the body. also transports waste products (c02,lactic acid) for removal
what makes up the circulatory system?
heart, blood, blood vessels
what is the function and location of the heart=
heart is a muscular pump that pushes 02 etc around the body, its is myogenic, size of a mans clenched fist,
lies behind sternum just left of centre between left and right lung
what is heart rate?
- is stimulated to contract by complex integrated systems
- hearts pace maker is SA node (sinoatrial node) initiates cardiac muscle contraction and is located in right atrium wall
structure of the heart
- made up of thick muscular walls (myocardium), divided into separate left and right halves
- right half receives blood from body and pumps blood to lungs
- left half receives blood from lungs and pumps blood to body
what is the atrium/atria?
- chamber that blood flows into 1st when entering either side of the heart
- atria receives blood via veins from parts of the body and pumps blood down in ventricles
what are atria?
- smaller than ventricles
- do not contract particlully hard
- the atria can fail to contract properly , most of the blood in the atria still flows into ventricles passively
average adult HR?
72bpm
what do ventricles do ?
supply a force to push the blood to its various destinations
what do left/right side of heart do ?
left-pumps contents to furthest parts of the body
right-pumps to adjacent lungs
heart valves how many, what do AV and semilunar valves do? =
- no of different valves around heart !
- AV (atrioventricular) valves separate atria and ventricles and prevent flow of blood back into atria during ventricular contraction
- semilunar valves prevent back flow of blood back to right (pulmonary)and left ventricles (aortic valve) during ventricular relaxion
ventricular contraction=
systole
ventricular relaxion=
diastole
describe the movement of blood through the 4 chambers of the heart?
- 02 blood from lungs enters left atrium via pulmonary vein
- moves down to left ventricle
- pumped to body via aorta (gaseous exchange here, co2 blood from veins to heart)
- co2 blood enters right atrium via vena cava
- passed down to right ventricle and pumped to lungs via pulmonary artery
- gaseous exchange here, c02 removed, o2 taken in
*cycle repeats!!
what are the 4 components of blood?
1) red blood cells
2) white blood cells
3) platelets
4) plasma
describe red blood cells and their function
- called erythrocytes
- in soft red marrow, contain protein haemoglobin (iron rich pigment gives it the red colour)
- body contains 240-270million red blood cells in every drop of blood
- blood volume around 40% red blood cells
describe white blood cells and their function
- called leukocytes
- produced in red bone marrow, is transparent, no haemoglobin
- part of immune system
- cells destroy bacteria/other harmful living organisms and removed damaged r diseased tissue
describe platelets and their function
- called thrombocytes
- are cell fragments not whole cells; assist prevention of blood loss from a damaged blood vessel by forming a platelet plug
- release chemicals proving blood clotting
- initial stage for repair for damaged tissue
describe blood plasma
- straw coloured liquid portion of the blood
- mainly water (91.5%) and salutes (8.5%) like nutrients, gases, enzymes, hormones
describe structure of blood vessels and how many types?
different types of vessel categorised by shape and function
- all blood vessels linked to form continuous circulatory loop
- 3 TYPES OF BLOOD VESSEL
what are the 3 types of blood vessel
1) arteries
2) capillaries
3) veins
what are the 2 sub categories of blood vessel
1) arterioles
2) venues
what is pulmonary circulation
circulation between heart and lungs
- pulmonary heart chambers are left atrium and right ventricle
- pulmonary blood vessels are pulmonary artery/vein
what is systemic circulation
circulation between heart and body
- systemic heart chambers are left ventricle and right atrium
- systemic blood vessel are aorta, inferior vena cava (carries blood from lower body, superior vena cava from upper body)
deoxygenated blood is ….. and appears ….. when viewed through blood vessel walls
dark red, blue
what colour is oxygenated blood?
bright red