OCR F214: Communication, Homeostasis and Energy - 17 June 2013

Thank you!

Want to revise

yeah. go on, you first.

yaya excited thank you!


Describe the structure of the liver (4 marks)

Sorry, went to have dinner.

The liver contains hepatocytes, sinusoids, hepatic vein duct. and hepatic artery and hepatic portal vein and pancreatic duct meet at the vein.

To be honest, I still have this topic to go. This is the only one which I am not confident with. as much.

Okay, let me ask you another question, you used the correct key words though!



Describe where and how ATP is made in Glycolysis (4)

ATP is made in the cyctoplasm of the cell in the stage of glycolysis. It is made during substrate level phosphoryaltion of ADP. This follows a series of stages in which glucose is phosphoryalated to glucose -6- phosphate. Then it changes into an isomer of fructose-6-phsophate. Then phosphorylatipn occus again to make hexose-1,6-bisphosphate. In these phosphorylation, ATP -> ADP and Pi. Two molecules of Triose Phosphate are made. This is then oxidised and 2NADH2 is made to make an intermediate product, which is then converted to two molecules of pyruvate by SLP.

Very good 4/4

My turn

Suggest why the ATP yeild may be lower than expected in respiration per mole of glucose.

1) because some ATP is used to actively transport the pyruvate molecule in cytoplasm into the matrix of the mitochondria.


2) ATP leakage as the protons diffuse into the (inner mitochondrial membrane )

3) some ATP is used as a shuttle for hydrogen atoms from the reduced NAD made in glycolysis to be transported into mitochondrial membrane

yup well done.

State how many ATP is made during oxidative phosphorylation and suggest where this process takes place (2)

24-26 and it takes place in the cristae.

Can I have some questions on NS, Homeostasis, Kidney please?

Just to clear some ambiguity in the OCR Textbook on pg95 figure. 3 Why is a "...dehydrogenase" used when a CO2 is released? Should it not be a decarboxylase? If you look at the subsection, Alcohol Fermentation, looking at bullet point 2, it says that the reaction is catalysed by a decarboxylase. Why do things have to be awkward?

That's wrong, it's meant to be decarboxylase I asked my teacher about it. The text part is right, the diagram is wrong

that's weird my book already says decarboxylase :s

24-26 and it takes place in the cristae.

Can I have some questions on NS, Homeostasis, Kidney please?

really?

Wow, either it's a conspiracy to make sure some students miss out in marks so they have a broad grade boundary or they made a mistake and amended it in an earlier edition which you have.

Have you looked in the diagram though?

Heres some..

haha much more likely to be the latter :P yep both diagram and the text say decarboxylase!

Oh, atleast I kept my eye open, Thanks!