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Various questions

  1. Aug 26, 2007 #1
    If Organisms need: energy source, water, minerals, vitamins. What type of environment is needed for growth?
  2. jcsd
  3. Aug 26, 2007 #2
    What factors help a host against infection?

    Totally confused on this...is it normal flora or flora???
  4. Aug 26, 2007 #3
    How do fevers help an infection?

    Okay, I understand with a fever: First the body heats up, the blood and lymph system makes a lot of Wt. blood cells to fight the infection. The increase in these white blood cells affects the part of your brain that controls your body temperature (the hypothalamus). This makes your body heat up, causing a fever. In the early stages of a fever you often feel cold and start to shiver. This is your body’s response to a rising temperature - the blood vessels in your skin tighten up (constrict), forcing blood from the outer layer of your skin to inside your body where it is easier to keep the heat in. The outer skin layer then becomes cool and your muscles start to contract. This makes you shiver. Shivering produces more heat and raises your temperature even more. In the second phase of a fever, the amount of heat you make and lose is the same. So the shivering stops and your body remains at its new high temperature. Your body starts to try and cool down so that your temperature can return to normal. The blood vessels in the skin open again, so blood moves back to these areas. You may sweat, as this helps to cool down the body....***how can I shorten this or is what I put even right???
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