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IAL Biology unit 5

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just read the article and find out the possible questions, like if you find a word that's in our specification, read everything about it!this book is so expensive, i don't think its worth it!i can sit for the exam at least five times instead of buying that book!
well the new EDEXCEL rule says that u can only repeat an exam only once.so i think the book might be a better bet
 
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can sum1 give an answre for this question.why do we shiver when we have a fever?
when we have fever we feel cold-
1. A part of your brain, called the hypothalamus, gets cold. It doesn't have to get very cold, just a little will be enough.
2. This part of your brain then makes your muscles shake. This way your muscles are moving, but you aren't running around. It works well.
3. This muscle shaking (shivering) makes a LOT of heat, can be as much as 3x as without shivering. If it is really cold, you won't be able to stop shivering until you go inside and get warm.
4. This will warm you up, and your hypothalamus. After a while you stop shivering.
 
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guys i still don't get the difference between the roles of the sodium-potassium pump and sodium-potassium gated channels.can sum1 plzzz xplain?
the pumps uses energy to actively transport Na+ out of the axon and K+ into the axon. it works so long as atp is present i.e all the time.
the voltage gated channels help in facilitated diffusion of these ions. they depend on the voltage difference i.e the electrical gradient along the membrane.
correct me if im wrong;)
hope that helps. :D(y)
 
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i don't know if it's correct, it's just a guess.
sprint athletes have more fast twitch muscles, so more muscle cells respire aerobically. so i think a increase in red blood cells wouldn't cause any benefits.
fast twitch muscles do not depend on aerobic respiration but on anearobic respiration. i guess epo increases O2 capacity. as fast twitch muslces dont need O2 they really dont require epo.
;)(y)
 
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when we have fever we feel cold-
1. A part of your brain, called the hypothalamus, gets cold. It doesn't have to get very cold, just a little will be enough.
2. This part of your brain then makes your muscles shake. This way your muscles are moving, but you aren't running around. It works well.
3. This muscle shaking (shivering) makes a LOT of heat, can be as much as 3x as without shivering. If it is really cold, you won't be able to stop shivering until you go inside and get warm.
4. This will warm you up, and your hypothalamus. After a while you stop shivering.
hypothalamus is the thermoregulatory centre. thermoreceptors sense drop in temperature and activate the heat gain centre in the hypothalamus. it sends impulses to the muscles to contract faster and more. so that heat is generated which will increase the temperature back to its normal value.
however it not only cause shivering but also activate other processes of the body to either produce heat or conserve it.
 
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192
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can sum1 give an answre for this question.why do we shiver when we have a fever?
this fever is actually hypothermia i.e drop in body temperature.
thermoreceptors sense drop in temperature and activate the heat gain centre in the hypothalamus. it sends impulses to the muscles to contract faster and more. so that heat is generated which will increase the temperature back to its normal value.the contraction of muscles is shivering.
however it not only cause shivering but also activate other processes of the body to either produce heat or conserve it.
 
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