How was Biology Paper 42

[fathimaash]

daaaaammmnnn i missed the last part :S :S :S :S
any way i may get 1 mark

Ya mayb

 

[mariyam95]

For Q1 part ii).....the one where they ask us to explain the shape of the graph after 30 degrees celsius.....i wrote that the plant will have to be a C3 plant and so the enzymes denature above 30 degrees thus decreasing rate of photosynthesis....

at 30 the rate of photosythesis was at maxmuim if enzymes denatures then it should get to zero :|

 

[freezingfires]

I wrote predicts the success of survival following implantation but doesn't predict the chances of successful implantation. And for then second disadvantage I wrote that the remaining embryos have to be discarded and how that presents as a ethical issue.

Wrote the same

 

[afoo.666]

for section B i chose 9, here are my points:

A) prokaryotic cell so smaller then eukaryotic cell, no nucleus, naked DNA, looped DNA, small circular strands of DNA called plasmids, cell wall made of peptidoglycans, may be protected by capsule, do not have double membraned organelles such as golgi body, and one more i think but i cant remember it

B) process called bioleeching, use thermophilic bacteria, bacteria must be able to cope with acidic conditions as H2SO4 produced, used on low quality ores where conventional is too expensive, bacteria are reused, family of bacteria called ferroxidans.

I wrote almost same.but dot you think its less fr total 15 marks?.

 

[mariyam95]

thats what i mean but i missed the last part :|
anyway its better than dividing 125 by 700 !

The question asked what percentage of the plasma was filtered right?

By your method,
12oo cm^3 blood -----> 700 cm^3 plasma
so 125 cm^3 blood -----> 72.9 cm^3 plasma.

The question wanted what PERCENTAGE of the plasma was filtered not the volume of plasma in 125 cm^3, so shouldn't it have been 72.9/700* 100 = 10.4% ?

 

[tasmiah2310]

For the key in the genetic cross, doesn't necessarily have to be 'W' right? :/

 

[terry jefferson]

at 30 the rate of photosythesis was at maxmuim if enzymes denatures then it should get to zero :|

yeah i had a doubt.....i wrote enyzymes denature as temperature increases above 30 degrees thus decreasing the rate

 

[terry jefferson]

For the key in the genetic cross, doesn't necessarily have to be 'W' right? :/

no it doesnt

 

[mariyam95]

yeah i had a doubt.....i wrote enyzymes denature as temperature increases above 30 degrees thus decreasing the rate

i dont remember the question but i guess t was asking ahy its at maximum at 30
so i wrote its an ezyme controlled reaction
enzyme K.e is high at thiss tempeture so enzyme activity is high .... bla bla bla

 

[terry jefferson]

Guys can I get the answer for the adaptations of the glomerular capillaries and podocytes for ultrafiltration??

 

[fathimaash]

Glomerular capillaries r made up of endothelial cells nd have large gaps allowin most of it to pass through and fr podocytes they r finger like projectors made up of epithelial cell nd so help in filtering nd blah blah blah

Guys can I get the answer for the adaptations of the glomerular capillaries and podocytes for ultrafiltration??

 

[tasmiah2310]

Guys can I get the answer for the adaptations of the glomerular capillaries and podocytes for ultrafiltration??

For glomerular capillaries, i wrote about the high pressure created by difference in diameter of afferent and efferent, causing the filtrate to be passed through basement membrane

And for podocytes from about finger like projections, increase surface area, more diffusion

 

[Jinkglex]

No, each point scores 1 mark for every question, so 15 total points = 15 total marks

capillaries had thin walls and large spaces in walls
podocytes were finger like projections which did stuff i've forgotten now

time lapse was helpful because it allowed best embryo to be selected, and disadvantage was even though 93% accurate, still had chance of failure, which could cause distress.

 

[afoo.666]

What was that we have to label in that PCT or DCT it was i guess cant remember

 

[mariyam95]

What was that we have to label in that PCT or DCT it was i guess cant remember

micovilli

 

[tasmiah2310]

Expecting the worst for Paper 5 -_-

 

[afoo.666]

micovilli

Ph.m

micovilli

Oh. I left it blank.

 

[Wanderer]

What was the answer for that Na/K pump question?
Why would the mRNA reduce in number and the previous part where they asked why the cells would survive if ion channels were closed?

 

[Wanderer]

For Q1 part ii).....the one where they ask us to explain the shape of the graph after 30 degrees celsius.....i wrote that the plant will have to be a C3 plant and so the enzymes denature above 30 degrees thus decreasing rate of photosynthesis....

I wrote that firstly the enzyme(Rubisco) will start losing the tertiary structure and get almost denatured at 50 C so Calvin cycle would reduce.
Secondly, due to high temperature, stomata closes to prevent transpiration and CO2 cannot enter,again reducing CO2 fixation.

 

[Amaryllis]

For glomerular capillaries, i wrote about the high pressure created by difference in diameter of afferent and efferent, causing the filtrate to be passed through basement membrane

And for podocytes from about finger like projections, increase surface area, more diffusion

same here what did u write for the question (which light dependent stage oxygen is produced) i wrote non cyclic - photolysis and the photosystem was type 2 right ?? and the question under it , i wrote because some oxygen is used in respiration