A level Biology: Post your doubts here!

[Student12]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s07_qp_2.pdf

PLEASE HELP ME WITH QUESTION 6 A ....

The cell surface membrane is 7 to 7.5 nm thick. You have to learn it. So the ans. is 7.0 nm.

 

[Student12]

AS BIOLOGY
9700 P2
M/J/03
Q4(b)

It would be easier for others to answer if you post the link of the paper

 

[Hussnain]

sir which year paper?

M/J/2003

 

[Hussnain]

It would be easier for others to answer if you post the link of the paper

http://www.xtremepapers.com/papers/...and AS Level/Biology (9700)/9700_s03_qp_2.pdf

 

[Hussnain]

Hussnain said: ↑

AS BIOLOGY
9700 P2
M/J/03
Q4(b)​

http://www.xtremepapers.com/papers/...and AS Level/Biology (9700)/9700_s03_qp_2.pdf​

 

[Student12]

Hussnain said: ↑

AS BIOLOGY​

9700 P2​

M/J/03​

Q4(b)​

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s03_qp_2.pdf​

The vascular bundles are situated towards the outside because it provides support and strength.

 

[huey ni]

please help to answer this question.
Which term describes the type of bonding responsible for stabilizing the secondary structure of a protein?

 

[confused123]

what are the colour changes of glucose when we add Benedict solution into it. like what's the order which shows the concentration. or put in another way. what will be the colour changes in chloro meter in ascending order. thanku very much.

 

[XPFMember]

what are the colour changes of glucose when we add Benedict solution into it. like what's the order which shows the concentration. or put in another way. what will be the colour changes in chloro meter in ascending order. thanku very much.

Aoa wr wb!
The colour changes from blue to green to yellow to orange to brick red.
the conc., u may may measure, for eg by seeing the time taken for the first sign of colour change to appear.

 

[Nibz]

VIBGYOR (the colours in Rainbow).
Violet - lowest concentration.
Red - highest concentration

 

[confused123]

Namaste
Thanks both of you. appreciate prompt response

 

[confused123]

http://www.xtremepapers.com/CIE/International A And AS Level/9700 - Biology/9700_s03_qp_1.pdf
q, 7 , 18 and 25. Thanks a lot.

 

[smartangel]

in the application booklet..aspects of human reproduction..page 50. it says next to the picture that it is imp to be able to explain why the tubules, which are all circular in cross-section, appear a variety of different shapes. so whats the answer to it?

 

[confused123]

AS BIOLOGY
PAPER 1
MCQ'S
7,16,19,22 AND 30

7 ) i dnt knw,

16) in mitosis homologous chromosomes are not present. and chromosomes number remains same. the chromosomes have to be identical. asexual reproduction


19) as later we grow bacteria for 5 generations in N14 so with the time N15 will disappear and will not pass on. n14 will be taken more readily i guess. u can see dat % of cells containing n15 is decreasing at a constant rate getting halved.

22) its a fact. memorize. its 2 pa to 6 pa in pulmonary arteries. it will be less saturated with oxygen

30) the volume of blood flow thru the muscles is less.

 

[Hussnain]

7 ) i dnt knw,

16) in mitosis homologous chromosomes are not present. and chromosomes number remains same. the chromosomes have to be identical. asexual reproduction


19) as later we grow bacteria for 5 generations in N14 so with the time N15 will disappear and will not pass on. n14 will be taken more readily i guess. u can see dat % of cells containing n15 is decreasing at a constant rate getting halved.

22) its a fact. memorize. its 2 pa to 6 pa in pulmonary arteries. it will be less saturated with oxygen

30) the volume of blood flow thru the muscles is less.

thanks

 

[XPFMember]

Assalamoalaikum wr wb!
for the role of glycoprotein, ms mentions 'for cell adhesion'...can someone please explain this point...

JazakAllahu Khairen!

 

[hassam]

in the application booklet..aspects of human reproduction..page 50. it says next to the picture that it is imp to be able to explain why the tubules, which are all circular in cross-section, appear a variety of different shapes. so whats the answer to it?

the tubulues myt be squashed or pressed out of shape during sslide preparation

 

[Nibz]

Assalamoalaikum wr wb!
for the role of glycoprotein, ms mentions 'for cell adhesion'...can someone please explain this point...

JazakAllahu Khairen!

Ws.

Glycoproteins serve to 'stick' cells to cells. This is what this point means.

 

[raamish]

Qp: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_s10_qp_11.pdf

Ms: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_s10_ms_11.pdf

i need help on qs 33,28,27,24,20,21,15,3

 

[confused123]

Qp: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s10_qp_11.pdf

Ms: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s10_ms_11.pdf

i need help on qs 33,28,27,24,20,21,15,3

3) area of field of view = Pi r square needs to be applied. so first lets see how much does one eye piece graticule division represents. 40 e.pg divisions equal to 0.1 mm on stage micrometer, i.e 0.1/40= 0.0025 , multiply this with the radius that is 50 divisions. and then multpily with thousand to get the answer in micrometers. um which is 125.

now 125 into 125 into pi is the answer. C

15) enzyme is made from protein. protease digests protein. i.e D.

21) its a fact. pentose sugars and phosphate are in equal number and DNA has adenine and thymine bases are equal as well.

20) in interphase chromosome number doubles. so the diagram is showing us the diploid number of chromosomes which is 8 , half or haploid will be 4. lock B option.

24) the mRNA formed from the template DNA original strand will be UCU, and then tRNA will have AGA I DON'T GET THIS. but someone answered this mcq on previous pages.

27) fungi will be absorb the water and will occupy the xylem vesseles. the h20 molecules will be unable to stick together and the water coloumn will break. mass flow is due to transpiration so fungi not influencing this mechanism. A looks right.

28) i cnt explain. look for diagrams in book, they might help

33) tidal capacity and vital capacity both will decrease as you know during exercise we can't take a lot of oxygen we r not breathing deep but we r breathing quick. lungs do not inflate to full capacity... A option. i know its not so convincing answer. would like someone else to better explain.