L10 Circulation 1 Flashcards
What is Ficks law
Rate of diffusion ∝ surface area*concentration difference/thickness of membrane
What do cells require and what do thay need to get rid of
Need nutrients and oxygen/
Rid of CO2 and nitrogenous compunds
What are the 3 components of a ciculatory system
Circulatory fluid, interconnecting vessels and a muscular pump (heart)
What are the 2 types of circulatory system
Open and closed
In an open circulatory system, what is the fluid, does it do and in what organisms is it found
Hemolymph
Hemolymph bathes body cells and organs
Arthropods and molluscs
In closed circulatory systems where is the blood and what organisms have them
Blood is confined to vessels
Annelids, cephalopods and vertebrates
What do arteries branch into and what do they do
Arteries branch into arterioles and carry blood from heart to capillaries
What are the sites of chemical exchange between the blood and interstitial fluid
Capillary beds
What do venules converge into and their function
Venules converge into veins and return blood from capillaries to the heart
How are Arteries and veins distinguished
Direction of blood flow and not O2 content
Single circulation system structure and organisms
One atrium and one ventricle
Bony fishes, ray and sharks
Double circulation organisms, and features
Amphibians, reptiles, birds and mammals
Oxygen rich and poor blood are pumped separately from right and left sides of heart
Maintains higher blood pressure that single circulation
Which direction do the pulmonary veins and arteries go in
Pulmonary Veins: lungs to heart
Pulmonary Artery: heart to lungs
what are the Atrioventricular valves
Tricuspid: right atrium and right ventricle
Mitral (bicuspid): left atrium and left ventricle
What are the semiluminar valves
Aortic: left ventricle and aorta
Pulmonary: right ventricle and pulmonary trunk
What is function of the heart valves
Ensure blood flows in the correct direction
What are heart murmurs caused by
EXtra sounds i.e. backflow of blood through a defective valve
Left atrium
Receives oxygenated blood from the lungs via the pulmonary veins (pulmonary circulation)
Left Ventricle
Pumps oxygenated blood via the aorta (systemic circulation)
Right Atrium
Receives deoxygenated blood from the body (systemic circulation)
Right Ventricle
Pumps deoxygenated blood to lungs via the pulmonary arteries (pulmonary circulation)
What is the cardiac cycle
The rhythmic cycle in which the heart contracts and relaxes
What is Systole and diastole
Systole - the contraction or pumping phase
Diastole - the relaxation or filling phase
Strucutre of the artia and ventricles
Artia - Relatively thin walls and serve as collection chambers for blood returning to the heart
Ventricles - thicker walls and contract much more forcefully
What are the 2 types of circulation in the human body
Pulmonary and systemic
Circulation system of fish
Two chambered heart
Single circulation system, blood leaving heart passes through two capillary beds (first gills and then systemic/ body capillaries) before returning to the heart
In fish ,the blood flowing in the systemic part of the circulation is at low pressure. Why is this ok
Fish are ectothermic so they have a relatively low metabolic rate
Circulation system of amphibians
Double circulation
Three chambered heart
Oxygen poor blood flows through a pulmocutaneous circuit to pick up oxygen through lungs and skin
Is there any mixing of oxygenated and deoxygenated blood in amphibians and reptiles
yes
Circulation system in reptiles
Double circulation
Three chambered heart
Circulation system in mammals and birds
Double circulation
Four chambered heart
Left side of heart receives and pumps oxygen rich blood
Right side of heart receives and pumps oxygen poor blood
