Circulation Flashcards
Phagocytes Job Look Nucleus Adaptations
Defence/ immunity
3 lobed nucleus
Engulf invading pathogen
Secret enzyme to digest DNA of pathogen
Red blood cell. Job Look Nucleus Adaptation
Oxygen transport Bio concave disc No nucleus (more space for haemoglobin to carry oxygen) Large surface area Packed with haemoglobin Smooth to slide through capillary tubes
Lymphocytes Job Look Nucleus Adaptations
Defence/ immunity
Large central nucleus
Under chemical signals from phagocytes, releases antibodies
Antibodies are precisely shaped to bind to antigen son the surface of the pathogen.
Heart
Right = deoxygenated
Atrium top, ventricle bottom
Right from body to lung
Left from lung to body
Valves
Cuspid stops blood returning to atria.
Semi lunar stops blood falling back into the ventricles from the arteries.
Hepatic artery/ vein
Heart to / from liver
Renal artery / vein
Heart from/ to kidney
Femoral artery/ vein
Heart from / to lower body
Hepatic portal vein
Intestine to liver
Vena cava
From rest of body to heart
Pulmonary artery
From heart to lungs
Pulmonary vein
From lungs to heart
Aorta
From heart to rest of body
Arteries around heart and associated problems
Coronary arteries. 4 main branches.
Atheromas (fat deposits)
To stop: exercise, blood cholesterol low, saturated fat low, avoid stress, don’t smoke, reduce salt
Arteries
Endothelium: delicate lining of cells
Narrow lumen
Thick layer of muscle tissue and elastic fibres and connective tissue.
High pressure blood away from heart usually oxygenated.
Branches into smaller arterioles.
Capillaries
Walls made of single cell layers
Very narrow lumen. Just 1 red blood cell thick.
Slow blood flow to allow time for diffusion.
Plasma can leak out of pores creating tissue fluid.
Form highly branched capillary ness in all tissues.
Veins
Endothelium Wide lumen Thin muscle layer Layer has no elastic fibres so no pulse Low pressure blood back to heart Usually deoxygenated Receives blood from smaller venules Has valves to assist blood flow back to the heart
How blood is helped to return to the heart.
Pocket valves in all large veins
Contraction of skeletal muscle especially in the legs.
Deep vein thrombosis
Prolonged activity + dehydration.
Clot in the vein which the body will eventually break down.
However can cause a pulmonary embolism, fragments if clot lodge in small arteries in the heart.
Coronary heart disease
Blood flow constricted by a plaque.
Small blood clot or thrombus= zero blood flow to cardiac muscle so that part of the heart will die.
Treatment for coronary heart disease
Bypass using some vein from the leg to bypass clot.
Balloon angioplasty, stent remains in place
Treatment for leaky valves
Mechanical, plastic cage with ball which moves up and down. Needs blood thinking and clotting drugs.
Biological valves, taken from pigs or humans. No drugs. Only lasts 15-20 years
Blood groups
Blood group-antigens-antibodies A-A- anti B B-B- anti A AB-A&B- none O-none- anti A&B
Blood donors
Unsafe if plasma antibodies bind to antigens causing blood to clot=fatal.
O is universal donor
