OCR Biology A2 F214/F215 exams June 2016

if anyone could tell me the importance of coenzymes in resipration I'd be so grateful, I understand what they do but the importance is what I don't get it at all?

They enable dehydrogenation reactions to occur by accepting hydrogen atoms, forming NADH. The role of NADH would be to donate hydrogen atoms at the inner mitochondrial membrane. These hydrogen atoms would split into protons and electrons. The electrons would then be pumped along the electron transport chain to form the proton gradient that drives chemiosmosis, subsequently producing the 30 ATP's! Hope that helps!

They basically do what normal enzymes can't. So in respiration for example you have loads of oxidation and reduction reactions and normal enzymes can't catalyse this
i don't know if this is useful but thats what i know :"

In the OCR book it says the blood is taken from a vein? (Now I think they usually join the vein and the artery to form one big strong blood vessel) I may be wrong though!

Can someone please explain the countercurrent multiplier mechanism- i still don't get it

if anyone could tell me the importance of coenzymes in resipration I'd be so grateful, I understand what they do but the importance is what I don't get it at all?

In the link reaction when pyruvate + coenzyme A turn into acetylcoenzyme A, this is important because in the Krebs Cycle following this, It is turned back to Coenzyme A and this initiates the whole Krebs Cycle. In general, coenzymes are just necessary for energy production.

I would recommend going youtube watching nottsast video on loop of henle he explained to me very well its easier to understand when you see how it works

whats the difference between a lobe and a lobule? (if any)

ok thanks

Can someone please explain the countercurrent multiplier mechanism- i still don't get it

For all those asking for the 2015 papers.

Can someone explain this question to me PLEASE!

Plants that live in the Arctic have a relatively short growing season in which the lightintensity is always relatively low. Many species growing in these conditions have a highlevel of anthocyanin pigments in their leaves. The combined effect of these redpigments with the green chlorophyll makes the leaves appear dark purple or black. Suggest why this adaptation is useful in increasing photosynthetic rates.

There's every possibility that something on Kidney Failure could come up - the advantages and disadvantages possibly.

Can someone please explain the countercurrent multiplier mechanism- i still don't get it