hello..hee..bio rep speaking..
i'm so sorry..hee..jus checked my email..n saw mdm tay's email..which was sent on 13 mar..hee..paiseh..was mugging so din touch com for e past few weeks..lolx..hee..hmm..the email say so.....
Hi Xiaohui,
Pls disseminate this email to rest of the class:
1. Please note there are some errata on the comparison of photosynthesis and respiration (attached). Mostly they are minor additions or clarifications marked out in red. The major mistake is the direction of proton pumping - (need to clarify this refers to which direction are protons pumped to generate the proton gradient): for respiration, it should be from matrix to intermembranal space (not the other way round). Sharp-eyed hawks among you may have spotted this already...
2. Supplementary material on polytene chromosomes attached too (FYI only)
3. In response to Xiaohui's question on why insulin promotes amino acids uptake and protein synthesis... do note that insulin exerts an overall anabolic effect in the body. In the fed state (after a meal), the levels of nutrients in the bloodstream (absorbed from the gut) tends to be high. Insulin promotes uptake of glucose, amino acids and fatty acids from the blood and their subsequent conversion into storage forms. Insulin increases protein synthesis, mainly by increasing mRNA translation - so this explains why aa uptake is increased. This contributes to the overall anabolic effect - the aim is to build up of storage forms of nutrients when they are available in excess. During times of fasting, when insulin levels drop while glucagon levels rise, the overall effect is catabolic - to break down these storage forms for use by the body. The balance now swings towards protein breakdown instead of protein synthesis.
Hope these help.
All the best for your block tests...gambatte ne!
Mdm Tay
hmm..err..i dunno how to attach files on blogs..hee..so i'll print the edited comparison between photosyn n resp for u all..as for the supplement material..those interested can sms me,call me or jus tell me in sch la..hmm..once again..so sorry for telling u all these after the bio paper..hee..anw,dun tink it'll be of much use even if i tell u all b4 the paper..hmm...am i right?!dunno..cant rmb e paper liao..lols..hee..but anw,still can learn for BT2,prelims n A levels yeah?hee..
hmm..jiayou for phy paper tmr..BT1 will b over soon..jiayou jiayou! =D
