Circulatory System Flashcards
what are veins? and properties
vessels that return blood to the heart
wide lumen
thin walls
have valves
blood at low pressure and carries deoxygenated blood except pulmonary vein
what are arteries? and properties
carries blood away from heart
no valves
narrow lumen
thick walls with muscle tissues and elastic walls
carries blood at high pressure
oxygenated blood is carried except pulmonary artery
what is a capillary?
walls with single layer of cells
substances can easily pass through eg: from blood to body cells
what does the right side of the heart pump?
deoxygenated blood to the lungs where it gains oxygen and loses carbon dioxide and returns to the left side of the heart
what does the left side of the heart pump?
oxygenated blood pumped around the whole body
the ventricular muscle is thicker to pump around the whole body
the heart muscle cells supplied with blood via coronary artery
how are the impulses of the heart contraction recorded?
using an electrocardiogram (ECG) which detects impulses using electrodes placed on the skin
what is the composition of blood?
plasma - contains red and white blood cells and platelets
in a healthy person there are more red blood cells than white
what does the plasma in the liquid in the blood do?
plasma contains dissolved ions,glucose , amino acids and also CO2, proteins like hormones and antibodies
what are the 2 types of white blood cells?
lymphocytes - produces antibodies and target bacteria and viruses
phagocytes - ingest and engulf pathogens
what do platelets do?
help clot at a wound site to stop blood loss and prevent microbes entering body
exchange surface needed in unicellular organisms?
have large SA:V
therefore can rely only on diffusion alone for gas exchange
why is a transport system needed in multicellular organisms?
need to get o2 to all cells
transport system does this quickly especially when there’s a lot of cells
have adaptations like a large volume of o2 can enter with one breath
how does the blood travel through the heart?
blood comes in from the right atrium from the body and moves into right ventricle
its then pushed into the pulmonary arteries into the lungs
after picking up oxygen blood travels back to heart via pulmonary vein into left atrium to left ventricle and then to body tissues from aorta
right atria>right ventricle>pulmonary artery>lungs>pulmonary vein>left atria>left ventricle>aorta
