Circulatory System in Animals Regents Biology 2008 2009

Circulatory System in Animals Regents Biology 2008 -2009

Feeding Energy Needs § Why do we need a circulatory system? u supplies in § _______________________ w ______________________ u waste out § ____________ w ___________ u need to pick up & deliver the supplies & wastes around the body Regents Biology § ____________

Circulatory System § Organ u _______ § Tissues & cells u ______________ § _______ u ______________ § _______ Regents Biology

Vertebrate Heart § 4 -Chambered heart u ______ (atrium) § __________ left atrium § collection chamber § receive blood u _________ right atrium § __________ § pump blood out Regents Biology right ventricle left ventricle

Evolution of circulatory system Not everyone has a 4 -chambered heart fish 2 chamber V amphibian 3 chamber reptiles 3 chamber A A V Regents Biology A V birds & mammals 4 chamber A V

Lub-dub, lub-dub § 4 valves in the heart u u flaps of connective tissue ______________ § Heart sounds u u ______________ “Lub” SL AV AV § force blood against closed AV valves u “Dub” § force of blood against semilunar valves § Heart murmur _____________________ Regents Biology u blood squirts backward through valve u

Electrical signals allows atria to empty completely before ventricles contract stimulates ventricles to contract from bottom to top, driving blood into arteries § heart pumping controlled by electrical impulses Biology § Regents signal also transmitted to skin = ____

atria empty into ventricles Cardiac Cycle How is this reflected in blood pressure measurements? chambers begin to fill pump (peak pressure) _________ fill (minimum pressure) 110 ______ 80 Regents Biology ventricles pump

Measurement of blood pressure hypertension = (high blood pressure) Regents Biology if top number > 150 or if bottom number > 90

Have a heart? Ask Questions!! Regents Biology 2006 -2007