Topic 1 Flashcards
(119 cards)
What processes cause CHD
Athlerosclerosis and blood clots. (due to high blood pressure, toxins and fat deposits)
What is a stroke
A stroke is a blood clot in the brain that cuts off blood circulation
Why is a circulatory system or a mass transport system needed
For mass flow, to overcome the limitations of diffusion
Who uses open cirulatory systems
Insects
How does an open circulatory system work
Oxygenated blood is pumped into cavities around vital organs for diffusion. Blood circulates in large cavities
Who has closed circulatory systems
Many animals and all vertibrates
What does a closed circulatory system contain
Tubes for the blood often vessels, high blood pressure with no cavities for faster transport of blood, either a single or double circulatory system and (in this order) arteries -> arterioles -> capilaries -> venules -> veins.
How does a single circulatory system work
Deoxygenated blood is pumped from the heart to the gils, diffusion of substances takes place and the blood oxygenates, the oxygenated blood flows through the body and back to the heart
How many atriums and ventricles do single and double circulatory systems have
Double = two of each Single = one of each
How does a double circulatory system work, and what components of the heart does the blood travel through
Deoxygenated blood from the right side of the heart is pumped from the heart to the lungs via Pulmanory artaries. The blood becomes oxygnated in the lungs and returns to the left side of the heart via the pulmanory veins. This oxygenated blood is sent to the body via the aorta, and returns to the right side of the heart via the inferior and superior vena cava.
What are the charge properties of water
It is a dipole because it has two equally charged polls. It is also a polar molecule because it has a uneven distribution of charge. Its negative ends are attracted to the positive ends allowing hydrogen bonds to form.
What are the solvent properties of water
Many chemicals can dissolve into it due to its dipole nature, this allows vital chemical reactions to take place inside the cytoplasm and allows for the transport of substances.
What are the thermal properties of water
Has a high specific heat capacity, therefore a lot of energy is needed to break the hydrogen bonds. This causes water to warm up and cool down slowly.
What causes the lub and dub sounds
Lub = atrioventricular valves Dub = semi-lunar valves
What does myogenic mean
It means that something can generate its own impulse
What do all vessels contain
Collagen, Elastic fibres, smooth muscle and endothelium
What is collagen
Collagen is fibreous proteins which make blood vessels stronger and durable
What are the properties of arteries and arterioles
Narrow lumen, thick muscle wall, no valves
What are the properties of capillaries
Lumen only allows blood cells through in single file, wall is only one cell thick for higher rates of diffusion. No valves.
How does blood flow through the arteries and arterioles
When blood flows into these vessels due to systole, the vessels dilate due to the infulx of blood, this is possible because of the elastic fibres. During diastole pressure is maintained due to the vessels constricting, this also smoothens the flow of blood, this is so there is a steady flow of blood in the smaller arterioles and capillaries.
How does the blood flow through the capillaries
The flow of blood is steady in the capillaries for more diffusion of substances, there is also high friction in the capillaries which reduces the rate of the flow. There is one close to every cell in the body.
How does the blood flow through the venules and veins
There is a low pressure, and blood flows steadily with no pulses, the flow is assisted by the skeletal muscle pump and breathing. Any backflow of blood is prevented by the semilunar valves.
What happens during atrial systole (phase 1)
Blood arrives in the atriums via the inferior and superior vena cavas (right), and the pulmonary veins (left) due to the skeletal muscle pump and breathing. The atriums start to fill with blood and pressure increases forcing some blood through the atrioventricular valves into the ventricles. When systole occurs the atriums contract to force more blood into the ventricles.
What happens during ventricular systole (phase 2)
There is a slight delay after atrial systole before ventricular systole takes place. Ventricles contract from the base of the heart upwards increasing pressure on the semilunar valves which open allowing blood into the aorta and the pulmonary arteries. This pressure causes the atrioventricular valves to close preventing the backflow of blood into the atriums.