Author Topic: Edexcel BIOLOGY Doubts!!!!  (Read 139671 times)

Offline MKh

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #435 on: May 16, 2011, 10:13:17 am »
anytime :)

Offline ayuwaza misaki

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #436 on: May 16, 2011, 05:37:24 pm »
Quote
can someone complete the remaining blanks for me please

Heart wall muscle is a special type of muscle called Cardiac muscle. This muscle can contract or relax without nervous stimulation and is thus described as _____________. To ensure that the cardiac cycle stays in sequence there is an in-built control mechanism. The wall of the right atrium contains a special region of muscle called the ______________ which sets up a wave of electrical activity causing the atrial walls to contract almost simultaneously. There is a band of fibres between the atria and ventricles which _______________ the wave of activity passing to the ventricle walls. The wave of activity is picked up by the ____________ situated in the septum at the junction of the atria and ventricles. The wave of activity then passes down the septum in the _________________ causing the ventricles to contract.


Thank you

the answers are in order:
myogenic
SAN (sinoatrial node)
Purkyne fibres
AVN (atrioventricular node)
heart (i'm not sure abt this one though)
« Last Edit: May 16, 2011, 05:40:14 pm by ayuwaza misaki »

Offline noor.h92

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #437 on: May 16, 2011, 06:09:55 pm »
Hello,

Im doing the January 2011 paper 3. can anyone help me with the first question, how do i draw the graph ?
« Last Edit: May 16, 2011, 06:13:45 pm by ~ The Golden Girl ~ »

Offline Amii

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #438 on: May 16, 2011, 06:12:21 pm »
How do we calculate the standard error and draw the error bar?

Could someone please help?

Thank you  :D

By my sweeett nephew ;D

Amelia

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #439 on: May 16, 2011, 06:57:33 pm »
How do we calculate the standard error and draw the error bar?

Could someone please help?

Thank you  :D

For standard error, read this link carefully. If you dont get it, I'll explain later.  :P
Error bar with example - http://www.ncsu.edu/labwrite/res/gt/gt-stat-home.html
« Last Edit: May 16, 2011, 06:59:40 pm by Amelia »

Offline guMnam

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #440 on: May 16, 2011, 06:59:24 pm »
can some one tell me wats the diff between c & d .. i mean are they in the same stage of mitosis ??

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Amelia

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #441 on: May 16, 2011, 07:03:55 pm »
can some one tell me wats the diff between c & d .. i mean are they in the same stage of mitosis ??

Not a huge difference. The first picture is early Anaphase - chromosomes starting to pull apart & the the second one is just Anaphase (the stage which occurs before telophase).

Offline Amii

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #442 on: May 16, 2011, 07:25:35 pm »
For standard error, read this link carefully. If you dont get it, I'll explain later.  :P
Error bar with example - http://www.ncsu.edu/labwrite/res/gt/gt-stat-home.html

Thank you :D but I can google too  :P
Standard deviation = ? = sqrt [(?((X-?)^2))/(N-1)]. What??  :-X ::) 

Anyway I will get it from my friend now - she finally woke up  :D

+rep for taking the pain .Thank you  :)



By my sweeett nephew ;D

Offline guMnam

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #443 on: May 16, 2011, 08:17:45 pm »
Thank you :D but I can google too  :P
Standard deviation = ? = sqrt [(?((X-?)^2))/(N-1)]. What??  :-X ::) 

Anyway I will get it from my friend now - she finally woke up  :D

+rep for taking the pain .Thank you  :)



By the way we dont need to noe all this stuff for unit 3 exam do we ?? :S i thought all tht part was in unit 6 =\

I <3 Challenges
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Offline guMnam

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #444 on: May 16, 2011, 08:21:25 pm »
Not a huge difference. The first picture is early Anaphase - chromosomes starting to pull apart & the the second one is just Anaphase (the stage which occurs before telophase).
and Thanks amelia.. so we say tht both of them are from anaphase yea ?? or one is early anaphase and 2nd is late anaphase?? (i guess both ans wud be correct )

any ways Thanks :)

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Offline Amii

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #445 on: May 16, 2011, 08:30:55 pm »
By the way we dont need to noe all this stuff for unit 3 exam do we ?? :S i thought all tht part was in unit 6 =\
Did you check the sample paper for Unit 3?The graph has 1 mark for drawing the error bar.  :)

 


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Offline guMnam

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #446 on: May 16, 2011, 08:35:00 pm »
no i didnt can u give me a link to it ??

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Offline rameeziiii

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #447 on: May 16, 2011, 09:45:55 pm »
what do you guys recommend doing in prep for the exam? do all the practicals or do the past papers?

Offline Blizz_rb93

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #448 on: May 16, 2011, 09:56:07 pm »
what do you guys recommend doing in prep for the exam? do all the practicals or do the past papers?
id say revise the practicals then solve pastpapers and time yourself for good time management thats all thats left to do, exam is tomorrow

Offline Amii

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Re: Edexcel BIOLOGY Doubts!!!!
« Reply #449 on: May 16, 2011, 10:31:50 pm »
no i didnt can u give me a link to it ??
It's there in the edexcel site but something seems to be wrong with that site.Anyway -attached  :D

By my sweeett nephew ;D