Term
| What are the main functions of the blood in terms of transport? |
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Definition
- transport of oxygen and nutrients to all cells of the body
- transport of carbon dioxide and other waste products away from the body
- transport of chemical messengers (hormones) to the cells |
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Term
| What is the liquid/nonliving part of the blood and what percentage does this make of the entire blood volume? |
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Definition
| Plasma, 55% of blood volume |
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Term
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Definition
| 91% is water, whilst the remaining 9% is dissolved substances including nutrients (glucose, amino acids, lipids), ions, gases, hormones, proteins and wastes |
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Term
| What are the two types of leucocytes? And how long do they live for? |
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Definition
1. Granulocytes - have a granular cytoplasm and a lobed nucleus
2. monocytes and lymphocytes - have a sperical nucleus and agranular cytoplasm
They live for a few days |
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Term
| What are the formed elements in the blood? What are they suspended in? |
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Definition
Cells and cell fragments - erythrocytes, leucocytes and thrombocytes
Suspended in the plasma |
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Term
| What colour is haemoglobin? and how does oxygenated and deoxygenated blood affect its colour? |
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Definition
haemogloobin is dark red/purplish
oxygenated blood (oxyhaemoglobin) is bright red in colour
Deoxygenated blood is dark red in colour |
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Term
| What 3 factors makes erythrocytes well suited to their functions? |
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Definition
1. they contain haemoglobin which is able to combine with oxygen
2. they have no nucleus so there is more room for haemoglobin molecules
3. they're biconave structure increases the surface area to volume ratio, allowing diffusion/gaseous exchange to happen at a faster rate and allows room for haemoglobin |
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Term
What percentage of carbon dioxide gas is dissolved in plasma?
What percentage combines with haemoglobin?
How is the remainder of carbon dioxide carried? |
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Definition
7-8% dissolved in plasma solution
22% combines with haemoglobin to form carbaminohaemoglobin
The remainder (about 70%) is carried as bicarbonate ions and is dissolved in plasma
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Term
Define and describe the heart's:
-location
-structure
-function |
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Definition
- A pump that pushes blood around the body, located in the chest cavity, between the two lungs
-size of a human fist
- The membrane is called the pericardium : it holds the heart in place, but allows it to move as it beats. It also prevents the heart from overstretching
The wall of the heart is made of a special type of muscle called 'cardiac muscle'
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Term
| Describe the role of blood vessels in circulation |
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Definition
| blood is pumped by the heart into the blood vessels, which carry the blood to the cells of the blood and back to the lungs and then back to the heart |
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Term
| What are the 3 main types of vessels? describe each |
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Definition
Arteries: carry blood away from the heart to the body (usually oxygenated), and channel into smaller artieries called arterioles
Veins: Carry blood to the heart from the body (usually deoxygenated), and channel into smaller veins called venules
Capilaries: tiny blood vessels which carry blood between cells. They are single / thin layered to allow diffusion/gaseous exchange to occur in and out of cells. They also provide a link between arterioles and venules to form a network |
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Term
| What is the Septum? (ventricuar septum) |
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Definition
| The heart muscle that separates the left and right side of the heart |
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Term
| What does systole refer to? and what types of systole are there? |
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Definition
cardiac muscle contraction
atrial systole and venticular systole |
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Term
What does diastole refer to?
and what are the types of diastole? (how many seconds each?) |
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Definition
heart muscle relaxation or filling.
There is ventricular diastole (4secs) and atrial diastole (7secs) |
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Term
| Decribe atrial systole - how long it lasts and what it does |
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Definition
| lasts for one second. Blood is forced from atria into ventricles. ventricles are in diastole at this stage. |
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Term
| Describe ventricular systole - how long it lasts for and what it does |
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Definition
lasts for 3 seconds.
It is cardiac muscle contraction which forces blood out of the ventricles into the pulmonary artery or aorta. at this point, the atria are in diastole |
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Term
| Describe the detailed function of arteries and how the structure may change for its function (particularly describe what happens during systole and diastole) |
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Definition
- they have thick, smooth-muscled walls that contain elastic fibres
-they have walls that stretch (during ventricular systole) and recoil (during diastole). This allows constant pressure to keep blood flowing.
- Artieries can make their lumen decrease in diamatre to redirect and channel blood flow to other organs/areas. This is called vasoconstriction
- Ateries can also make their lumen diametre increase to allow more blood flow to an area. This is called vasodilation
Atrerioles can also alter their diamatre to regulate blood flow to capillaries |
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Term
| Describe the function of veins and their regualtion of blood flow |
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Definition
-carry blood to heart
- carry deoxygenated blood (except pulmonary vien)
- have valves positioned to stop backflow of blood
- cannot change their diametres to regulate blood flow
- venules are smaller veins that carry blood from tissue capillaries to eventually link with larger veins |
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Term
| What are capliaries and what makes them effective for their function? |
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Definition
they are small, microscopic blood vessels found between cells
they are single layered to allow transport of oxygen/nutrients to cell and wastes away from cells through diffusion
they provide a link between arterioles and venules |
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Term
| Describe the function of thrombocytes |
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Definition
-they produce tiny fibronogen fibres to form a net. This traps other blood cellls to form a blood clot to stop excessive bleeding
- During clot formation, fibronigen is converted to tough, stringy fibrin by an enzyme called thrombin |
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