B/Z - Comparing Circulatory Systems, Mammalian Transport Flashcards
What is mass transport?
Mass transport: the movement of materials at equal rates or as a single mass; accounts for the long distance travel of fluids in living organisms; includes the movement of blood in circulatory system of animals.
Identify 2 exchange sites in a vertebrate
Gills/lungs and tissues
What is the key difference between open and closed circulatory systems?
Open:
Open-ended vessels pump fluid into intercellular space, NO circuit from heart to body and back again.
Closed:
Fluid is contained in vessels, making a full circuit for blood to pass through from the heart to the body and back again.
Pulmonary circuit
Carries blood between HEART and LUNGS (takes up oxygen)
Systemic circuit
Delivers oxygenated blood around the body
What are aortic arches (in invertebrate closed c. systems)?
Contracticle aortic arches are accessory organs for blood propulsion (supporting the propulsion action by the dorsal blood vessel).
What are the respective roles of dorsal and ventral blood vessels (in invertebrate closed c. systems)?
The dorsal vessel receives blood from the lateral vessels and carries it towards the head.
The ventral vessel carries blood posteriorly (to the rear) and distributes it to the segmental vessels (lateral).
Double circulation systems occur in what kind of animals?
All vertebrates other than fish
What type of circulatory system do fish (bony fish, rays and sharks too) have?
Closed, single circuit
Where does blood go after being oxygenated by the lungs (for vertebrates)?
To the heart, which then pumps the oxygenated blood through a systemic circuit to the body.
When does mixing of oxygenated and deoxygenated blood occur?
In amphibians and most reptiles, where the heart is not completely divided.
What prevents reverse blood flow in a fish heart?
One-way valves (sinoatrial and atrioventricular valves)
Where does the blood flow to immediately after it has passed through the gills in a fish?
Blood passes from the gills to body tissue.
Where does the blood flow immediately after it has passed through the lungs of a mammal?
Blood returns to the HEART after the lungs.
Why does blood flow at a higher pressure in the systemic circuit of a mammal compared to that of a fish?
Because on the way back from the lungs, the blood is propelled by the heart in a mammal; whereas, in fish, the blood flows directly from gills to body tissue.
