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A level Biology: Post your doubts here!

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Does anyone here know how to move the stage micromter on the microscope.... like how to move it? so that it can line with the the eye piece graticule??????
 
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Does anyone here know how to move the stage micromter on the microscope.... like how to move it? so that it can line with the the eye piece graticule??????
Just like you move any specimen that is being inspected.... By using the controls on the microscope.
 
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how can the intial rate reduce? if the active site doesnt change shape the initial activity of the enzyme in this case is not affected
As there is an inhibitor its harder for substrate to leave. So rate of reaction reduces
 
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Just like you move any specimen that is being inspected.... By using the controls on the microscope.
oh ok, so the round circular "noob" on the microscope also move the stage ? I have seen the videos mostly, showing how to adjust the specimen?I
anyway thank you for replying.. very kind of you :)
 
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10. Which of the following genotypes would produce the smallest number of different gametes if the alleles are assorted independently?
A) aa BB Dd
B) AA BB DD
C) Aa Bb DD
D) Aa BB DD
E) Aa Bb Dd

11. Which of the following processes can decrease the genetic variation in natural populations?
A) recombination B) immigration C) mutagenesis D) inbreeding E) hybridization

12. Which of the following structures present in the embryos of higher plants develops into primary leaves of seedlings?
A) epicotyl B) endosperm C) radicle D) hypocotyl E) cotyledon

can anybody please answer those and maybe explain ?
 
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10. Which of the following genotypes would produce the smallest number of different gametes if the alleles are assorted independently?
A) aa BB Dd
B) AA BB DD
C) Aa Bb DD
D) Aa BB DD
E) Aa Bb Dd

11. Which of the following processes can decrease the genetic variation in natural populations?
A) recombination B) immigration C) mutagenesis D) inbreeding E) hybridization

12. Which of the following structures present in the embryos of higher plants develops into primary leaves of seedlings?
A) epicotyl B) endosperm C) radicle D) hypocotyl E) cotyledon

can anybody please answer those and maybe explain ?
10. B
11. D
12. E
 
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View attachment 60966 can some one explain this ASAP plss???
Q.2. As the question says that '4 different amino acids' you'll need 4 different tRNAs to carry those different aminoacids.. Since tRNA can be reused, we can have 4 tRNAs and still be able to translate mRNA. So the answer must be 'A'
14. As you must be familiar with the fact that cytosine combines with guanine and adenine with Uracil. If 20 % of bases are cytosine, the percentage of guanine must be the same i.e. 20. S the remaining total percentage is 60.. which is of adenine as well as thymine. Since they've got to be complementary base pairing, their percentage too will be the same i.e. 30! So when 30% of adenine will link up with mRNA nucleotides , 30 % of the bases in mRNA would be uracil
 
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Q.2. As the question says that '4 different amino acids' you'll need 4 different tRNAs to carry those different aminoacids.. Since tRNA can be reused, we can have 4 tRNAs and still be able to translate mRNA. So the answer must be 'A'
14. As you must be familiar with the face that cytosine combines with guanine and adenine with Uracil. If 20 % of bases are cytosine, the percentage of guanine must be the same i.e. 20. S the remaining total percentage is 60.. which is of adenine as well as thymine. Since they've got to be complementary base pairing, their percentage too will be the same i.e. 30! So when 30% of adenine will link up with mRNA nucleotides , 30 % of the bases in mRNA would be uracil
thanks alot :) do u have any idea about the 53rd question as well????
 
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