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A level Biology: Post your doubts here!

XPFMember

XPFMember

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As-salam-o-alaikum wa-rehmatullahi wa-barakatuh!!

Well I remember reading somewhere that for some cells (probably plant ones) go directly into meiosis 2 without cytokinesis....may be that's the reason...m nt sure though!
 
rz123

rz123

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consider the following statements about biological communities
1. their members share a common gene pool
2.the community remains stable even though some physical aspect of the environment may undergo change
3.they possess predictable kinds of species in predictable proportions
4. interactions between their members are more frequent within the community than between theri members and those of neighborijng communities.

which two of the above statements apply to all stable biological communities?
ms ans is : E: 3 n 4 but how? need lil explanation thank u
 
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hassam

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see OXYGEN being a non-polar molecule will simply diffuse out into the tissue fluid down the conc. gradient through phospholipid bi layer.......bt u have got a problem wid glucose .....since its much larger and polar it can't just simply diffuse via the lipid bilayer.......fortunately in case of capillaries there are are tiny pores b/w adj. epithelial lining of capillary so glucose seeps out via pressure filtration
 
Noor

Noor

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Salamo Alaikom, you lot. I really find this thing dead helpful! ._. Haha, I mean thank youu. :3
Anyhow, long story short, I'm doing Bio AS this year. We got a really nice lovely teacher, the thing is? She barely knows stuff and her notes are kinda retarded! xD ADD to that, the book we're using hasn't got a lot of details, so I was wondering if there's anywhere besides http://www.biologymad.com/ I could get good detailed simple notes from. :/ Thank you.
 
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hassam

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no......it will not be passive transport since the processes of endocytosis and exocytosis require energy derived from ATP!
 
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hassam

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What is genetic drift? can anybody explain and what the hell it has to do with speciation
 
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hassam

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one of disadvantage of GM crops is development of superweeds.......can somebody explain how gm crops cn lead to development of superweeds?
 
XPFMember

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larina said:
PAPER 5!!
What is meant be dependent and independent variables???
Click to expand...


As-salam-o-alaikum wr wb!

in simple words...independent is the thing you are changing, and dependent is the thing which is being affected by the change u made...

eg u want to see the effect of temp on the rate of reaction....so u'll take different temp...in otherwords temp is what u r changing so it'll be the independent variable...and the rate is being affected by temperature..so it is the dependent variable!
 
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