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AS Biology P1 MCQs Preparation Thread

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aoa wr wb

umm explain this one plz

View attachment 12750
To get BEST ESTIMATE OF ENZYME ACTIVITY the ;
1.enzyme must be present,
2.its substrate must be present
3.No inhibitor must be present.

If above 3 conditions are set the highest possible rate of reaction of an enzyme can be determined.

If the blood is sterilised obviously the enzyme will be denatured so low enzyme activity :( poor enzyme :(
 
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okay thanx for your help
however part A the ms says it occurs during prophase:(
part C the ms says it is only the peptide bond that will form:S
:confused:
Ooops, so sorry. I made a mistake over there. Disulphide bridge will only occur in tertiary and quatenary structure. Since the ques says btwn 2 amino acids, so it's a primary structure. Hence, only peptide bond is involved. Part A i'm not sure then :(
 
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I am getting alot of problem in solving magni fication questions
magnification = size of image/actual size of specimen


For example, the actual size of a plant cell is 150 micrometers, but when you measure the cell with a ruler, you find out that it is 6 cm. First, convert both measurements to the same units. In this case, 6 cm = 60,000 micrometers. So the magnification is 60000/150 = x400
 
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AsSalamoAlaikum Wr Wb!!!


screen-shot-2012-06-11-at-7-09-34-pm-png.12724


^ It's B....umm..i dunno i remember solving this question..n i kida learnt the answer :D

screen-shot-2012-06-11-at-11-20-48-pm-png.12725


^when amino acids join, it's the peptide bond that is formed. Hence it's D.

screen-shot-2012-06-12-at-12-11-59-pm-png.12726


^I don't know...is it D?
Erm, you got it right for 2 only :( Erm, for 1, the ans is D. It can't be having the same water potential in lake water. It'll restrict the entry of water since there's a presence of cell wall. The vacuole will push against the cell wall. :) As for 3, the ans is A. For choice 1, bond breaking will happen when the two DNA strands are broken, and the bond linking mRNA and DNA template will be broken too. For option 2, bonds are formed when the free nucleotides join to the DNA template and when the DNA template rejoins the DNA strand. bonds are reformed too. Option 3 & 4 only happen once.
 
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According to the fluid-mosaic model, the more unsaturated phospholipids there are (i.e. phospholipids with a double bond in them), the more "fluid" the membrane is. In cold conditions, we all get stiffer, right? Even membranes! So if membranes want to be less stiff in the cold, they should increase the ratio of unsaturated phospholipids to saturated ones.
 
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A pyramid of energy shows the energy of an organism in a trophic level. So to get that, you should multiply the biomass of one individual by the number of individuals (to get the total biomass)
The results are:
P: 1000
Q: 50
R: 1
S: 900000

Arrange them in a pyramid, and you'll find out that the answer is B
 

thu

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Netproduvctivity = respirationenergy/light energy * 100%
i.e 5000/1000000 * 100 % = 0.5% :D
why would net primary productivity involves respiration energy (5000) not the energy that gets passed on to herbivore (1200)?
 
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magnification = size of image/actual size of specimen


For example, the actual size of a plant cell is 150 micrometers, but when you measure the cell with a ruler, you find out that it is 6 cm. First, convert both measurements to the same units. In this case, 6 cm = 60,000 micrometers. So the magnification is 60000/150 = x400

And how to calculate stage micrometer questionss:mad:
 
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What is the difference between sunken stomata and stomata located in the grooves?
 
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And how to calculate stage micrometer questionss:mad:
There are questions when they put a tiny meter calibrated in 0.1mm divisions right above a graticule with 100 units. In this case, 0.1 mm normally take up 40 units. So if 0.1 mm takes 40 units, 1 unit would be 0.1/40 = 0.0025 mm = 2.5 micrometers in length.
 
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