26. Circulation and Gas Exchange Flashcards
what is the main difference between gastrovascular cavity and circulatory systems?
gastrovascular cavity is surrounded by a body wall made up of 2 layers of cells and the fluid inside the gastrovascular cavity is continuous with the environment. - simple animals circulatory system transports fluids throughout the body powered by the heart
what is the main difference between an open and closed circulatory system?
in an open circulatory system, haemolyph surrounding the body tissues also act as the circulatory fluid. TOGETHER in a closed circulatory system the fluid surrounding body tissue is SEPARATE of blood acting as the circulatory fluid
what is the advantage (1) and disadvantages (2) of an open circulatory system?
advantage: less energy to use
disadvantages: less efficient transport - slower no regulation flow of hemolymph to different organs
what are 2 advantages and 1 disadvantage of a closed circulatory system?
advantages:
- more efficient transport of gases and nutrients to tissues allow animal to be larger and more active
- distribution of blood can be altered depending on tissue requirements
disadvantage: more energetically expensive
what is the general scheme of vertebrate cardiovascular systems? (heart)
the heart has one or two atria, the atria are smaller, thinner walled chambers for RECIEVING blood returing to the heart
has one or two ventricles ventricles are larger, thick walled, musclar chambers for PUMPING BLOOD out of the heart.
what is the circulatory system of a fish like?
chambers, circuit, disadvantages
fish have a two chambered heart with 1 atrium and 1 ventricle.
single circuit of bloodflow
bloodflow: ventricle > gill capillary bed (gas exchange) > systemic circulation (tissue cappilary beds) > atrium
what is the circulatory system of an amphiban?
chambers, circuits
three chambered heart with 2 atriums and 1 ventricle.
two circuits of blood flow - blood passes through the heart twice on each trip around the body
PULMOCUTANEOUS CIRCUIT! takes blood from the heart to the lungs and skin for gas exchange
advantage: blood is pumped by the heart again after it looses pressure passing through lung/skin capillary beds. oxygen rich blood transported quickly to organs
what is the circulatory system of reptiles (excluding birds)?
chambers, circulation, circuits (2), advantages
three chambered heart - 2 atria and 1 ventricle
double circulation
pulmonary circuit takes the blood to the lungs for gas exchange
systemic circuite take blood to the tissues of the body
advantage: division of the ventricle into two cavites so no mixing occurs (closed circulation)
what is the circulatory system of mammals and birds?
chambers, circulation, advanage
4 chambered heart with 2 atria and 2 ventricles
no mixing of oxygen rich and poor blood (left side of heart recieves and pumps only oxygen rich blood and the right only recieves and pumps oxygen poor blood).
advantage: resotres pressure to the system after blood passed through lung capillary beds - essential for endothermy.
