-
We need your support!
We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
Click here to Donate Now (View Announcement)
bio p42
- Thread starter boy2011
- Start date
Aloo007 said:Can some1 tell me when it said how is maize adapted to reduce photorespiration what did you have to write? I just explained bundle sheath cells and all that
I think i really messed up that 15 mark Q about Maize
>Basically, you have to write how the arrangement of the mesophyll ring cells, how the are right above the bundle sheath cells (in the inner ring), being a effective barrier to oxygen from air. But that's half the story, you have to mention how PEP carboxylase joins Co2 with PEP to make the malate which is used to transfer CO2 down to the sheath cells for running the Calvin cycle.
>Did you write why in hot dry climate photo-respiration occurs too much?
I gave that in such conditions, the atmospheric CO2 content is low compared to other dense ecological regions' CO2 content. But one of my friends wrote that light intensity powers the light dependent stages of photosynthesis, thereby producing tons of O2 within the leaf structure, there by oxidizing RuBP to wastage. What do you think? I think my friends' answer then contradicts the O2 shielding concept, as the sheath layers have chloroplasts, and chloroplasts are the site of Calvin and light dependent cycles, how can O2 be produced in sheath cells as mesophyll ring cells are there to shield against it?
I am sorry that I am asking more questions than your answer.
- Messages
- 582
- Reaction score
- 113
- Points
- 53
@madan159 u can download it from here..
- Messages
- 582
- Reaction score
- 113
- Points
- 53
@hassam: sure i ll c wat i can do but if u need anything specific let me no
- Messages
- 4,291
- Reaction score
- 6,457
- Points
- 523
i want all details for bio 42 how to study for it...
- Messages
- 582
- Reaction score
- 113
- Points
- 53
@ both of u; da piece of advice would b not to worry too much cux frankly speakin bio is da easiest of da 3 science subjects n need minimal effort. The best book to follow dat ll b comprehensive n coverin almost al da needs of da syllabus ll b mary jones one along wid da application booklet, ofcourse…
U need to check da syllabus to c wat is required of u n prepare accordingly…
Moreover if v look into it chp wise here ll b ma personal opinion – any one can hav a prob wid it but it worked 4 me
Respiration: mary jones ll cover all u need to no… must c da cycles n pathways clearly n also try to memorixe da no of diff molecule synthesized n used in each pathway cux in j1o 42 dere wx a question bout no of NADH produced in Krebs cycle… dere is a table in both mary jones n biological science dat covers it… den must no dat whenevr question bout oxidative phosphorylation is asked chemiosmosis also needs to b described cux it is interlinked to it … also in plants u need to no n may already no dat anaerobic reaction pathway is same as that of yeast ie alcohal is produced not lactic acid… common sense but still… dere wx a question bout it in pprx…
Photosynthesis: again follow mary jones … structure of chlorophyll n pathways r imp as usual along with adaption of leaves n mesophyll cells .. have come in section B. the hill reaction is imp from ppr 5 point of u n u can cover it in prac skills in detail if u like…
Meiosis : Crossses r important .. practice dem much… make hypothetical cases by urslf n make crosses… practice dem from pprx much as sometimes more den 2 alleles r involved dat causes confusion… da insulin production is also covered in later chp so u can cover it dere in more detail… no causes of mutation n examples of it sickle cell anaemia n others… sickle cell anaemia is most imp n is mormally interlinkd wid malaria in questions if u notice da trend in pprx … dis concept is xplained in selection n evolution topic n detail… chi square test is imp as well n easier n I think dey gv da formula if ques is asked but it also needs practice which us hd do…
Selection n Evolution: don’t know y but I luv dis chp.. anyhow dis needs memorixin ability of urs… remember da examples diff stabilisin mechanisms n all… speciation topic is very imp where geaographical isolation n speciation thru polyploidy is discussed… u can get da concept of polploidy in later chp as well… but do dis chp well… dere r graphs in biological science where stabilisin mechanisms operation is xplained… u can look into dem..
Homeostasis: Most boring chp evr written *yawn*…. Wat can I say … evrythin is imp… in excretion ultra filtration n selective reabsorption, role of ADH n loop of henle … nervous system conduction of action potential n how da stimulus of diff intensity r recognixed… concept of threshold frequency n all… synapses… u can do it from biological science… more functions r given which ll ensure better marx scorin… den hormonal control… blood sugar control… its basic n simple n mary jones cover it just fine… n den plant growth regulators… only interestin thin in ma opinion … do this part well… rmbr da functions n all … I hv some notes point wise on da fuction of each.. I ll look into dem n type dem sometime n upload dem…
Biodiversity: appliaction booklet n mary jones ll suffice… no bout da reasons of extinction n ways to avoid or cure it… in pprx named examples r given.. ofcourse no 1 can memorise all the examples so u jst need to no da basic reasons dat fit evrywhre… like habitat loss… competition… diseases n so on… bt must pay attention as to where da organsm is livin n wat causes all da problems… like problems which exist for elephants obviously wont apply to crab word to word but theme for both ll b da same… easiest marx to score howevr…!
Genetechnology: hated dis chp… do it from application booklet n if extra info needed go for mary jones n cystic fibrosis is good in biological science… best of luck cux da concept of electrophoresis n finger printin ws snore enducin … :|
Biotechnology: mary jones is better for it.. but do read da application booklet… pay attention to da processes cus dis year immobilixed enzymes came n how to make sodium alginate beads n all… no da diff n prefenrence of batch culture over continous culture n monoclonal antibodies n disease treatment n diagonistic testin…
Crop plans: application is good n covers almost all… here polyploidy concerned wid wheat production r xplained… also gv mary jones a read … remember da adaptations of C4 plants n also rice growth in paddy fields.. golden rice too…
Reproduction: mary jones sucx here… do it from biological science… make a table of hormones involved dere site of production site of action feedback control… it ll help u b4 ppr wen u ll need quick review… go thru application booklet… need to pay attention to da labellin involved as well… it came dis year… n den go thru da techniques involved like IVF n others n moral n social limits from mary jones …
So here s da piece or should I sy monologue of advice from ma side… oh yeah do pprs as well… ofcourse… n u ll b more den prepared to take on da ppr… as u can see no more den dese books r needed to score a good grade n its not much wen u actually do it compared to how it sounds here… best of lcuk!
SORRY IF I MADE U DOZE OFF WID DIS
U need to check da syllabus to c wat is required of u n prepare accordingly…
Moreover if v look into it chp wise here ll b ma personal opinion – any one can hav a prob wid it but it worked 4 me
Respiration: mary jones ll cover all u need to no… must c da cycles n pathways clearly n also try to memorixe da no of diff molecule synthesized n used in each pathway cux in j1o 42 dere wx a question bout no of NADH produced in Krebs cycle… dere is a table in both mary jones n biological science dat covers it… den must no dat whenevr question bout oxidative phosphorylation is asked chemiosmosis also needs to b described cux it is interlinked to it … also in plants u need to no n may already no dat anaerobic reaction pathway is same as that of yeast ie alcohal is produced not lactic acid… common sense but still… dere wx a question bout it in pprx…
Photosynthesis: again follow mary jones … structure of chlorophyll n pathways r imp as usual along with adaption of leaves n mesophyll cells .. have come in section B. the hill reaction is imp from ppr 5 point of u n u can cover it in prac skills in detail if u like…
Meiosis : Crossses r important .. practice dem much… make hypothetical cases by urslf n make crosses… practice dem from pprx much as sometimes more den 2 alleles r involved dat causes confusion… da insulin production is also covered in later chp so u can cover it dere in more detail… no causes of mutation n examples of it sickle cell anaemia n others… sickle cell anaemia is most imp n is mormally interlinkd wid malaria in questions if u notice da trend in pprx … dis concept is xplained in selection n evolution topic n detail… chi square test is imp as well n easier n I think dey gv da formula if ques is asked but it also needs practice which us hd do…
Selection n Evolution: don’t know y but I luv dis chp..
anyhow dis needs memorixin ability of urs… remember da examples diff stabilisin mechanisms n all… speciation topic is very imp where geaographical isolation n speciation thru polyploidy is discussed… u can get da concept of polploidy in later chp as well… but do dis chp well… dere r graphs in biological science where stabilisin mechanisms operation is xplained… u can look into dem.. Homeostasis: Most boring chp evr written *yawn*…. Wat can I say … evrythin is imp… in excretion ultra filtration n selective reabsorption, role of ADH n loop of henle … nervous system conduction of action potential n how da stimulus of diff intensity r recognixed… concept of threshold frequency n all… synapses… u can do it from biological science… more functions r given which ll ensure better marx scorin… den hormonal control… blood sugar control… its basic n simple n mary jones cover it just fine… n den plant growth regulators… only interestin thin in ma opinion … do this part well… rmbr da functions n all … I hv some notes point wise on da fuction of each.. I ll look into dem n type dem sometime n upload dem…
Biodiversity: appliaction booklet n mary jones ll suffice… no bout da reasons of extinction n ways to avoid or cure it… in pprx named examples r given.. ofcourse no 1 can memorise all the examples so u jst need to no da basic reasons dat fit evrywhre… like habitat loss… competition… diseases n so on… bt must pay attention as to where da organsm is livin n wat causes all da problems… like problems which exist for elephants obviously wont apply to crab word to word but theme for both ll b da same… easiest marx to score howevr…!
Genetechnology: hated dis chp… do it from application booklet n if extra info needed go for mary jones n cystic fibrosis is good in biological science… best of luck cux da concept of electrophoresis n finger printin ws snore enducin … :|
Biotechnology: mary jones is better for it.. but do read da application booklet… pay attention to da processes cus dis year immobilixed enzymes came n how to make sodium alginate beads n all… no da diff n prefenrence of batch culture over continous culture n monoclonal antibodies n disease treatment n diagonistic testin…
Crop plans: application is good n covers almost all… here polyploidy concerned wid wheat production r xplained… also gv mary jones a read … remember da adaptations of C4 plants n also rice growth in paddy fields.. golden rice too…
Reproduction: mary jones sucx here… do it from biological science… make a table of hormones involved dere site of production site of action feedback control… it ll help u b4 ppr wen u ll need quick review… go thru application booklet… need to pay attention to da labellin involved as well… it came dis year… n den go thru da techniques involved like IVF n others n moral n social limits from mary jones …
So here s da piece or should I sy monologue of advice from ma side… oh yeah do pprs as well… ofcourse… n u ll b more den prepared to take on da ppr… as u can see no more den dese books r needed to score a good grade n its not much wen u actually do it compared to how it sounds here… best of lcuk!
SORRY IF I MADE U DOZE OFF WID DIS