circulation 7

Question 1

diff betweenn fish and mammals/birds

Answer 1

birds+mammals=4 chambered, 2 circuits, fish=2 chambered, 1 circuit

Question 2

fetal heart in avian and mammals

Answer 2

not involved in gas exchange in utero

-only fully divided after birth, allows blood to bypass pulmonary circuit

Question 3

amphibian an non-crocodile reptile heart

Answer 3

double circulation, but undivided circulation

amphs: 1 outflow vessel with SPIRAL VALVE
reptiles: ventricle undivided, one outflow vessel to lung, 2 to systemic circulation

Question 4

crocodile heart

Answer 4

2 atria, 2 ventricles, and 3 outflow vessels
right ventricle: 1 outflow to lung, 1 to systemic; left vent: 1 outflow to systemic
-left and right aorta joined immediately outside the heart by ductus arteriosus
-when holding breath cog valve cuts off outflow to lungs, so all blood goes through systemic

Question 5

what occurs when losing blood?

Answer 5

-decreased barorecptors firing causes increased symp output and norep release, which causes vasoconstriction, increase force of contractinos and heart rate to increase MAP

Question 6

MAP and exercise

Answer 6

large increase in cardiac output Q and massive vasodilation in skeletal muscles, plus CNS override arterial baroreceptors to allow MAP increase