A level Biology: Post your doubts here!

[yuliana95]

Q) Explain how vaccination can control disease?
---> Vaccine contains the micro organisms living or dead..when vaccines are injected, it gets into the body and body immune system recognize it as a foreign body.....the specific B and t Cells divide mitotically to form a clone.......which produces many antibodies.....and memory cells....!! antibodies find the pathogens and invade them..whereas memory cells make the body safe from the attack of pathogen the next time later...!!


Well..is this answer ok to this question...if the question was for 3 marks?

I think should be ok..

 

[hassam]

Macrophages only cut the pathogens up to display antigens or they also engulf pathogens by phagocytosis?

they do carry out phagocytsis for sure!!!.....as far as displaying the antigen thing.....i had a gr8 pic showing it.....lmme chek if i have got it now

 

[hassam]

 

[nano9595]

mrpaudel antigen presentation is considered incomplete phagocytosis

 

[Emily793]

hey guys i really need help can anyone advice me how to revise my AS level bio in 2days?? :Yahoo!: :Yahoo!:

 

[rz123]

hmm dats damn easy. Use Mary Jones Cambridge revision guide ..if u dnt have it then use it from here studyguide.pk

 

[Dayyanah]

hey guys i really need help can anyone advice me how to revise my AS level bio in 2days?? :Yahoo!: :Yahoo!:

two days?? :shock: isnt that phy p2?? im sitting for bio p2 on 18th

 

[mrpaudel]

GUys...one query.....While we are doing p5....for QN1....we are asked to write a procedure for an experiment that how we'll do....that usually carries 8 marks...!! now..i wanna know if we write the answer for that question in solid points or...as in para??

 

[XPFMember]

As-salam-o-alykum!

Well, I think you should write in paragraph form

the points you shud include in 8 marks question like these:

-independent variable(s)
-dependent variable
-control variable(s) and how to control them
-procedure: how the apparatus will be used, etc.
-reliability,( must be atleast 3 repeats for each set of readings...)
-safety precaution (any 'one' required!)

 

[memyself15]

hey, can anyone tell me from where to study applications? my teacher forbade us to study from mary johns book and application booklet.

 

[mrpaudel]

Lol..may i know why? ur teacher did so....strictly speaking...do study from application booklet....!! that will b more than enough..!! and..look at the Mary Jones book while u are revising..

 

[memyself15]

Lol..may i know why? ur teacher did so....strictly speaking...do study from application booklet....!! that will b more than enough..!! and..look at the Mary Jones book while u are revising..

she says there are mistakes in both

 

[mrpaudel]

Well..m student...so..i dont know how much mistakes are there...but yeah..our course book and mary jones vary in some of the things...like..small things...!! that is not a big deal....!! read the book and mary jones..and if u find there's two things written in two books..there's the internet.. and..as far as application booklet is concerned, i dont know what mistakes are there...but..Mark Scheme strictly follows whats written on the application booklet...so its better u learn the application booklet by heart...!!

 

[mrpaudel]

i dont know about other books from which u can prepare for...why dont u ask her only...where can we prepare for it......she may tell u...!!

 

[mrpaudel]

Somebody plz make the question clear to me...and then answer plz...!!

 

[mrpaudel]

Enzymes are globular proteins. State what is meant by the term 'Globular' ....actually..globular means spherical shaped...

But the ms says
-spherical/ball shaped
-has tertiary structure
-water soluble
-polar groups on outside..

What the hell...they are asking the meaning of term...and..water soluble..polar groups on outside..how far this si fair guys...!!

 

[Emily793]

they expect us to have phd in biology! or read out their minds huh!! :crazy: ppl

 

[mrpaudel]

yeah....i wonder..they are so strict in some of the questions....!! if the answer deviates a little..no reward....but...they are free to do anything...!! crazy ppl..

 

[nano9595]

i m freaking out about the exam tomorrow i just feel that i m going to mess things up
gud luck to u all :good:

 

[Emily793]

me 2 got p2 tomorrow wish u luck guys!! hope cambridge pity us this time!! :good: