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A level Biology: Post your doubts here!

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Can i just know that In the disease chapter, there is a lot given about mental diseases and physical and how to readthe health charts(in bradfield and essential bio), is it a part of syllabus? Can i skip it?

And can someone please explain me the pressurechanges graph in the heart chapter in detail? Thank you!
 
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CAn someone help me with ho0w to find the uncertaininty after finding the length of specimen??
thje question is on June/o7/p32
 
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Hi PhyZac
Well, cell 3 is a xylem vessel, whilst cell 2 is a "normal photosynthesising cell" and cell 1 a phloem cell. so you would expect that the water potential in cell 3 to be much less negative than the other cells because it contains water mainly. cell 2 will be less negative than cell 1 as cell 1 has a high conc. of sugars so has a less water potential. so the answer there must be A only.

for the second question according to me is the goblet cell because it releases a great deal of mucus, so it is bound to contain smooth endoplasmic reticulum (structure responsible for release of proteins.

Hope my answer helped u and good luck. :)
Oh thank you so much...! Jazaki Allah khairan.. May Allah reward you for your help. May you get the highest grade in this life and hereafter. Good luck.
 
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Oh thank you so much...! Jazaki Allah khairan.. May Allah reward you for your help. May you get the highest grade in this life and hereafter. Good luck.
Ameen
You're welcome.
If u hav more doubts, u can still ask me. I've already completed my A levels.
Thanks 4 ur wishes. god bless you. (y)
 
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CAn someone help me with ho0w to find the uncertaininty after finding the length of specimen??
thje question is on June/o7/p32
Hi Hassan.

Well, uncertainty is found using the smallest division of the instrument u used to measure divided by 2. For instance if u used a ruler, the smallest div. is 1 millimetre, so the uncertainty will be +- 0.5 mm
P.S I haven't had a look at the question, i just told u the way of doing it, now apply the same logic specifically to the question.

Hope my answer helped u. :)
 
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Hi Hassan.

Well, uncertainty is found using the smallest division of the instrument u used to measure divided by 2. For instance if u used a ruler, the smallest div. is 1 millimetre, so the uncertainty will be +- 0.5 mm
P.S I haven't had a look at the question, i just told u the way of doing it, now apply the same logic specifically to the question.

Hope my answer helped u. :)

But using this method the answer is not correct???/ :(
 
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Asslamu Alikum Wa Rahmatullahi Wa Barakatoho

This is an A2 question , sister Amy Bloom

In paper 5 i have come across this question, i am in little doubt how to do it. So can anyone give me a simple sketch of how to draw this.

qq.PNG
 
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Can i just know that In the disease chapter, there is a lot given about mental diseases and physical and how to readthe health charts(in bradfield and essential bio), is it a part of syllabus? Can i skip it?

And can someone please explain me the pressurechanges graph in the heart chapter in detail? Thank you!

Hi. I hope i'm not too late in answering ur doubt. Go to the syllabus year u're are taking part of the exam. I think u can skip it but still check, i dunno when u'll be givin the exam.
 
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THank you so much Jazaki Allah so much!!!!!!!!!!!!!!!!!! May Allah reward you Ameeen

Thanks Alot....May Allah give you the highest results in this life and hereafter AMeen.
Ameen & u're welcome.
thanks 4 ur good wishes and may Allah bless you with distinctions =]
 
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Can somebody help me with this question?

Which eyepiece and objective lens combination of a light microscope enables you to see the
greatest number of cells in the field of view?
Eyepiece Lens | Objective Lens
A: x5 | x10
B : x5 | x40
C: x10 | x10
D: x10 | x40
 
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Can somebody help me with this question?

Which eyepiece and objective lens combination of a light microscope enables you to see the
greatest number of cells in the field of view?
Eyepiece Lens | Objective Lens
A: x5 | x10
B : x5 | x40
C: x10 | x10
D: x10 | x40
Asslamu Alikum Wa Rahmatullahi Wa Barakatoho.

What is the answer in marking scheme?
I think it is A
 
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The answer is A, but why is it A?
See...
A: x5 | x10
B : x5 | x40
C: x10 | x10
D: x10 | x40

those are the magnification..! the larger the magnification....the bigger u see..! but the less u see...! I mean wen u take smallest magnification tht is A u see many cells but sooo small!
while in large like D u see less no of cell but bigger...get it?
 
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