WJEC biology BY4 11/01/2013

Ahh i thought glycolysis too :L that was a mean question, and 4 marks for it! I think the w came out both times right after the carbons reduced in number, if it was ATP what other evidence was there for it? (I thought co2)

Glycerol doesn't go in kerbs.... I thought it went in at triose phosphate too... But it specified '3 carbon compound' so I put pyruvate as there was no arrow pointing to triose

Also W was co2... Every time a substance loses a carbon it loses a co2 molecule!


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It said afterward, "what enzyme is used for it"? Or something similar. I too put co2, but becuase I did not know the enzyme I just put ATPase.

I think it wanted decarboxylase (for co2)

Ohh ok, is that even in the spec or text books?

I know, I put co2 too. But I did not know that "enzyme" question afterward.

Also, glycerol when broken down from fat does go into Krebs as triose phosphate.

Yeah decarboxylase.... But triose phosphate isn't in the krebs cycle....


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The endorsed text book states "glycerol forms a 3 carbon sugar and enters the krebs cycle as triose phosphate as an intermediate.

The endorsed text book states "glycerol forms a 3 carbon sugar and enters the krebs cycle as triose phosphate as an intermediate.

Overall, I thought it went okay, but we'll see in March I guess.

For the numbers I think I put:
2,6
1
1

And W was CO2, the enzyme was Decarboxylase.

The 8 mark table confused me mine, bloody WJEC...

I quite likes the table! But there was one I got stuck on... Where the final electron is accepted in a chloroplast... It's accepted by NADPH2 but does this happen in the stroma or thylakoid space?


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Yeah, that's what confused me. I went with Stroma + Matrix but that in turn confused me about 'where H+ are pumped through the membrane', because the arrow for chloroplast was pointing at the thylakoid space rather than the membrane <.<

Agreed, a lot of my answers were hugely ambiguous. I feel like it could be an E or if the boundaries are low a B. I thought the respiration thing was in the bag but now that I think about it I reckon I ****ed it up. I put the one about "glycerol going in as trios phosphate" in glycolysis, only to remember as soon as I walked out the door it goes in the Krebs cycle.

Also, how dare they represent the "w" tag labeling the Krebs cycle as ATP, a few people in my school said it was ATP but I thought it was Co2? If it was ATP then that's very mean, they did not even specify if it was one cycle or two? Bull****.

Ahh I went for thylakoid and matrix... Hmmm... Yeah! I can't remember now about that one haha


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what did people say for the importance of ATP???

I assumed the question was asking about the uses of ATP in the cell but I also mentioned what properties made it useful because I wasn't really sure.
For the uses you could say DNA replication, active transport, protein synthesis, muscle contractions...