biology paper 1 doubts

[athaan]

Here's another question from me!
Still from MJ2012, haha. http://olevel.sourceforge.net/papers/9700/9700_s12_qp_11.pdf

Number 39, please.
Answer is C.
I need an explanation, I don't fully understand the concept behind biomass and energy value. :s

 

[BettyBoop]

the answer is A and i dont really get it?

 

[BettyBoop]

no clue at all some1 plz explain answer is A

 

[ZohaibAsad]

Non-reducing sugar needs to be hydrolysed by the addition of an acid to break the bonds and make it a reducing sugar. The greatest difference is observed in A showing the greatest amount of non-reducing sugar is present in A when tested with Benedict's solution

 

[InnocentAngel]

OH ok thank you soo much! I thought it said the water potential of the CELLS will become less negative...

Lol i just read yr question and made the same mistake as you. Optical illusions xD

 

[InnocentAngel]

View attachment 18146no clue at all some1 plz explain answer is A

Take 55 - 30 u get 25 . then substract for B C D . in the same way. A gives a greater value. This value u calculated by substracting is the mass of the non-reducing sugar .

 

[Ashiq Sookarry]

Reducing sugar test non reducing sugar test
-ve +ve non reducing sugar present
+ve +ve non reducing sugar absent
+ve +ve (higher intensity than 1st one) R.S and N.R.S

 

[InnocentAngel]

What is the difference between these :
Endodermis
Epithelium
Epidermis
Endothelium

 

[Ashiq Sookarry]

endodermis is found in t.s root. epidermis is found in lower and upper epidermis in t.s leaf and t.s stem. epithelium is found in cilia. and endothelium is squamous epithelium that is one cell thick

 

[Kumkum]

Please help me with question number 5.
http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_12.pdf
i don't understand this...please show me any calculations that you might need to be able to answer this...
Thnx!

 

[Ashiq Sookarry]

I think B is the answer.
80 eyepiece division(eyepiece graticule)=0.2 mm
4 epd(chloroplast width)=0.01mm
1 mm=1000 um
0.01 mm= 10um

 

[Kumkum]

I think B is the answer.
80 eyepiece division(eyepiece graticule)=0.2 mm
4 epd(chloroplast width)=0.01mm
1 mm=1000 um
0.01 mm= 10um

yep the answer is B....thnx!!

 

[Kumkum]

Another question:
http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_12.pdf
question 8....why is the answer A?

 

[Ashiq Sookarry]

it is the formula of dissacharide. check ur notes. it is the same for all dissacharides.

 

[Kumkum]

it is the formula of dissacharide. check ur notes. it is the same for all dissacharides.

oh...i thought you just use the formula of glucose and then you add them since there are two molecules of glucose and that's why i chose my answer as C
thnx

 

[Amy Bloom]

Can somebody explain me this

 

[athaan]

Can I have help on ON2005? http://www.xtremepapers.com/papers/...and AS Level/Biology (9700)/9700_w05_qp_1.pdf
For question number 24. I do not understand the calculation at all. Answer is B.

And kinda different from the question I asked above.. does the stomata of a plant likely to close when the transpiration rate is high?

 

[BettyBoop]

View attachment 18168
Can somebody explain me this

they did mention that " zones less than 13mm show the presence of resistant bacteria" and 1 and 5 did not reduce to below 13mm over 5 week period

 

[InnocentAngel]

Why is the answer D ?
Are there really antigens on the surface of phagocytes ?
From the cambridge book it says that there are antibody receptors on white blood cells.I just dont get it !

 

[Amy Bloom]

they did mention that " zones less than 13mm show the presence of resistant bacteria" and 1 and 5 did not reduce to below 13mm over 5 week period

Silly me! (*facepalm*) thank you mate.