Topic 1 Flashcards
What are diseases of the heart and circulation known as?
Cardiovascular diseases (CVDs)
What is the alternative to a circulatory system in smaller organisms to move substances around the organism? Define it.
Diffusion - movement of molecules/ions from a high concentration to a low concentration.
In which organisms is diffusion usually enough to meet their requirements?
Unicellular
Differentiate between open and closed circulatory systems (4)
1) O = insects, C = all vertebrates
2) O - blood circulate sin large open spaces, C -enclosed tubes (blood vessels)
3) O - substances diffuse between blood and cells, C -higher pressures means more efficient at delivering substances around body
4) C = larger animals, more active than O
Which blood vessels does blood travel through from the heart to cells in the body and back to the heart again ? Put them in order.
Heart => Arteries => Arterioles => capillaries => Cells => Venules => Veins => Heart
What ensures that blood flows in one direction?
Valves
What’s the main difference between a single and a double circulatory system?
S - has ONE ventricles and ONE atrium - blood passes once in a circuit
D - has TWO ventricles and TWO atria - passes twice through
How do single circulatory systems work? (3)
1) heart pumps deoxygenated blood to gills
2) gas exchange - CO2 from blood into water, O2 from water int blood
3) blood from gills flows around body then back to heart
Show the flow of blood in a double circulatory system, starting at aorta.
Aorta => Body => Vena Cava => R. Atrium => Atrioventricular valve => R. Ventricle => Semilunar valve => Pulmonary Artery => Lungs => Pulmonary Veins => L. Atrium => AV valve => L. Ventricle => SL valve => Aorta
What are the 2 types of Vena Cava?
Superior - from head and arms
Inferior - lower body
Do water properties (pg 8)
(Pg 8)
Name the 4 blood vessels that take blood to and from the heart/cardiac muscle.
R. Coronary Artery - to, Oxygenated blood
R. Coronary Vein - from, Deoxygenated
L. Coronary Artery - to, O blood
L. Coronary Vein - from, DO blood
What are the differences between Arteries, Veins and Capillaries?
See worksheet in folder!!
A - narrow Lumen, Thick walls, more collagen, smooth muscle and elastic fibres, no valves
V - we’d lumen, thinner walls, less collagen and smooth muscles, fewer elastic fibre, has valves
C - ____ lumen, single cell wall,
What are the functions of collagen, elastic fibres and smooth muscle in blood vessels?
C - tough fibrous protein, makes vessels strong and durable
EF - allow stretch and recoil
SM -allow constriction and dilation
Explain how blood moves through vessels. (6)
1) during systole (heart contracts), blood forced into ARTERIES.
2) During diastole, artery walls recoil behind blood. Pushes blood along length of artery as walls stretch and recoil.
3) arterioles => capillaries
4) blood travels slower due to narrow lumen, allows exchange from blood to cells
5) capillaries connect smaller arteries to veins
6) skeletal muscles surrounding veins contract to push blood towards heart through valves.
