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biology paper 1 doubts

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Net primary productivity = energy absorbed - energy lost in respiration
energy absorbed = 1,000,000 - 990,000 = 10,000
energy lost in respiration = 5,000 (shown in the diagram)
Net primary productivity = 10,000 - 5,000 = 5,000
Percentage of light energy converted to net primary productivity = (5,000/1,000,000) x 100% = 0.5%
 
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Net primary productivity = energy absorbed - energy lost in respiration
energy absorbed = 1,000,000 - 990,000 = 10,000
energy lost in respiration = 5,000 (shown in the diagram)
Net primary productivity = 10,000 - 5,000 = 5,000
Percentage of light energy converted to net primary productivity = (5,000/1,000,000) x 100% = 0.5%
thank you!
 
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I think that would be because amylase is an enzyme and enzymes are proteins by nature. The DNA maps out the basic protein formation and hence the answer is A. Hope I helped! :)
ohh thank you! I just realized the option said amylase, i misread it as amylose the whole time. -.-
Can't afford to make such silly mistakes in the actual exam..but thank you!
 
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I'm not sure if it's mentioned in the AS Biology book, but the square of the stroke volume is directly proportional to the ventricular end-diastolic volume.
that's kinda confusing, because the answer is D. if it's directly proportional, shouldn't it be C? or there's a limit?
 
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I think that would be because amylase is an enzyme and enzymes are proteins by nature. The DNA maps out the basic protein formation and hence the answer is A. Hope I helped! :)
Also do you know why the answer to question 24 is C? Once again, thanks!
 
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I don't get this question ! why is it not c ?
The stroke volume should logically increase when the volume of blood in the ventricles increases, but the straight line indicates a linear relationship. It cannot be linear as a certain volume of blood is never expelled from the ventricles.
 
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I don't get how to do this.
Please help.
Thanks..
 

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that's kinda confusing, because the answer is D. if it's directly proportional, shouldn't it be C? or there's a limit?
I deleted my post. Here is exactly what I know:
Stroke volume = end systolic volume - end diastolic volume
End systolic volume = volume of blood after a contraction
So even after the ventricle contracts, there will still be some blood left over (maybe not all the blood made it through past the semilunar valve and went back to the ventricle).
 
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