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A level Biology: Post your doubts here!

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t
Acha tw here's the thing ..

First of all as they've given 0.1 mm which is equal to 100 um
If u count the number of units in between the eye piece graticule.. They are 40 units in total
So that means 40 units = 100 um

Now measure the length as in the units using the micrometer scale given.. That is almost 4 units
Now cross multiply

40 units = 100 um
4 units = x

Answer is 10
hanks
 
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18 - Ah I remember this one... cheeky one. Question says FOUR KINDS OF Amino Acids, thus maybe the same tRNA can bring them back and forth? Four different AAs need only four types of tRNA, and maybe a few tRNA molecules make more than one trips...
Answer - 4

16 - Google tells me that pairing up happens only in meiosis, and mitosis does not involve reduction of chromosome number
Answer - A (not sure can u check marking scheme and let me know???)

7 - measurement question. I can't do now but I can tell you that the minimum distance is where the rbc touches the capillary wall to the alveolar wall. And then u divide by 5000 to get the answer.

4 - when the cell and the solution have the same water potential, there is no movement of water. Thus the length of the cell does not increase or decrease. Thus the initial/final length value should be 1
Use the graph, and read off the corresponding concentration value...
Answer - C (0.45 moldm-3)

Thankyou :D
 
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Acha tw here's the thing ..

First of all as they've given 0.1 mm which is equal to 100 um
If u count the number of units in between the eye piece graticule.. They are 40 units in total
So that means 40 units = 100 um

Now measure the length as in the units using the micrometer scale given.. That is almost 4 units
Now cross multiply

40 units = 100 um
4 units = x

Answer is 10
Which question is this?:p
 
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