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12 Cards in this Set
- Front
- Back
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what are the three main factors that affect the need for a transport system? |
-size -surface area to volume ratio -level of activity |
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Explain why animals above a certain size or level of complexity required specialised systems for transport and exchange |
As body mass increases the surface area to volume ratio decreases as this occurs diffusion becomes too inefficient and slow to provide raw materials quickly enough to all of the cells of larger animals, Mass transport Systems are required to transport materials to and from where they are needed. |
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Why is there a need for transport system? |
To allow animals to grow to a large size they need a range they need A range of tissues and structural support, larger animals have a surface area that is not large enough to supply all the oxygen and nutrients needed by the internal cells. |
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Why is the level of activity and important factor when it comes to having a need for transport system? |
If the animal was very active its cells need a good supply of nutrients and oxygen to supply them energy for movement. |
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What are three good features of a transport system? |
-must have A fluid to carry nutrients/oxygen around the body -must have a pump to create pressure which will push the fluid around the body -must have an exchange surface enabling oxygen/nutrients to enter the blood and leave it. |
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What two things will an efficient transport system have? |
-tubes/vessels to carry the blood -two circuits, one to pick up the oxygen, one two deliver it to the tissue. |
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What is meant by A pulmonary circulation? |
-Circuit that carries blood to the lungs to pick up oxygen. |
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What is meant by systematic circulation? |
Circuit carrying oxygen/ nutrients around body tissue. |
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what are the advantages of a double circulatory system? |
-The heart can increase pressure of the blood after it passed through the Lungs, which means a quick bloodflow.
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Which type of circulation carries blood at a higher pressure? |
Systematic circulation. |
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what are the disadvantages of a single circulatory system? |
BP reduce as blood passes through tiny capillaries in the gills= slow blood flow limiting rate at which oxygen/nutrients are delivered to a respiring tissue. |
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Why might an animal have a single circulatory System? |
May not be very active. |
