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Check the 'Glossary' in Mary Jones Biology Book. Do the ones that are in AS syllabus.
Oh yeah, thanks a lot.
Bio last-minute revision notes, anyone? o.o
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Check the 'Glossary' in Mary Jones Biology Book. Do the ones that are in AS syllabus.
FROM SOURCE TO CELL C-
consider the companion cell first,where there is active loading of sucrose taking place.
H+ ions are pumped from the companion cells to mesophyll cells containing sucrose by active transport using ATP as an energy source.
As a result the H+ conc builds up in the mesophyll cells generating a potential difference across the membrane.
The H+ ions then move back into the companion cell down a conc. gradient through carrier proteins co-transporting sucrose molecules.
The sucrose molecules then move through the plasmodesmata into the sieve tube element(cell C)
FROM CELL C TO SINK-
When the sugar enters the cell C, due to low water potential being set up water enters by osmosis.
This builds up hydrostatic pressure.
At sink sugar is being used up( for respiration, conversion of sucrose into glucose and fructose)
This creates a pressure gradient between the source and the sink, causing mass flow of solution in phloem sieve tubes from source to sink.
thankuhttp://www.sparknotes.com/
http://revision-notes.co.uk/A_Level/
http://www.mrothery.co.uk/
Cambridge revision guide is also handy.
LOL wth man.s05: 14th) you can see that at B the graph is not steepest. the gradient is low. its not the optimum temperature. k.e of enzyme and substrate will get low at this point. whereas A its not far from the start of reaction so at this pooint bonds will be formed for enzyme substrate complex to be build upon...
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s05_qp_1.pdf
Q (14): Why not pick B as the correct one?
I know the difference between Anaphase and Telophase, but when it comes to real diagrams I can't tell them apart, for example page 6, Fig3.1
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w09_qp_21.pdf
The markscheme says the diagram is anaphase instead of telophase, can someone explain why
bite me!LOL wth man.
The real reason it's not B is because Q is not the highest temperature! The question is trolling you. Look where the highest temperature is, and this is where the KE will be highest.
it means the total fluid moves at once. whole of it moving..What does mass flow of solution mean?
can someone please explain why triglycerides release more energy on respiration than carbohydrates. This question has been repeated more than once, but i don't understand the points in the mark schemes, what is the chemistry behind it???
only Nitrogen CycleSomeone explain to me the Ecology Cycles which are in our syllabus (Nitrogen Cycle, and I think we have Carbon Cycle too).
AsSalamoAlaikum Wr Wb!Oh yeah, thanks a lot.
Bio last-minute revision notes, anyone? o.o
Uh... KE would increase regardless of the activity of the enzyme. Even if the enzyme is completely denatured and we continue to increase the temperature the KE would also continue to increase. KE only plays a role in the enzyme activity before the optimum temperature is reached in giving the molecules enough (activation) energy to form ES complexes.bite me!
ok so if the temperature will be highest at the end then enzyme will be denatured till then. i think that the enzyme activity increases twice for every 10 degree rise in temperature until optimum temp is reached. explain.
Type of immunoglobulins...i don't think so (not sure though)Does anyone know if we have to remember the types of immunoglobulins (A, G, M and E) and their functions? Also the 6 different ways antibodies help aid defense?
As far as I know, antibiotics affect the synthesis of the bacterial cell wall and bind to bacterial ribosome, thus because viruses do not have cell walls, the antibiotics can't act on them!hi
why is the antibiotics non effective on viruses?
and is the co2 transport included in the syllabus or i should only know the bohr's effect?
for the issue of CO2 transport, this is what it says in the syllabus:hi
why is the antibiotics non effective on viruses?
and is the co2 transport included in the syllabus or i should only know the bohr's effect?
hi
why is the antibiotics non effective on viruses?
and is the co2 transport included in the syllabus or i should only know the bohr's effect?
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