unit 5, Aerobic respiration and glycolysis Flashcards
where does glycolysis occur?
cytoplasm
what are the stages of glycolysis?
1) glucose (6C) is phosphorylated by x2 atp going to x2 adp +pi to generate glucose phosphate which have 2 phosphate groups adding onto each end of glucose (6C)
2) glucose phosphate is highly energised and highly reactive so it turns into x2 TP(3C)
3) x2 pyruvate (3C) is made by the oxidation of TP. in this step x2NAD becomes x2NADH as it gains a H from TP, and x2 ADP becomes x2 ATP.
why is it a net gain of atp?
- as the x2 ATP used in the beginning of glycolysis are being made again
what are the products of glycolysis?
x2 NADH
x2 net gain of ATP
x2 pyruvate
where does the link reaction and krebs cycle occur?
in the mitochondrial matrix
how do reduced NADH and Pyruvate go from cytoplasm to the mitochondrial matrix?
via active transport
what are the stages of the link reaction?
1) pyruvate (3C) from the link reaction is oxidised by the loss of a h+ and turns into acetate (2C) having a loss of 1 carbon dioxide
2) acetate (2C) combines with coenzyme A to form acetycoenzyme A (2C)
how many times does the link reaction occur?
x2
what are the products of the link reaction?
x2 acetycoenzyme A
x2 c02 released
x2 reduced NAD
what are the stages of the krebs cycle?
1) (from link) acetylcoenzyme A (2C) reacts with 4 carbon molecule toproduce a 6 carbon molecule. during this, when co-enzyme a is released it is recyled to be used again in the link reaction.
2) A 4 carbon molecule is generated by a series of redox reactions , x3 recuced NAD , reduced FAD and ATP ( by phosphorylation). there is a loss of 2C
how many times does the krebs cycle occur?
twice
where does oxidative phosphorylation take place?
-mitochondrial inner membrane, cristae
what are the total products from the first three stages?
-10 reduced NAD
-2 reduced FAD
what molecule is mostly made in oxidative phosphorylation?
ATP
what is the process of oxidative phosphorylation?
1) reduce coenzymes carry hydrogen to the oxidative phosphorylation stage, in the form NADH for example. The hydrogen atom that has been carried is split into electrons and protons.
2) these electrons are passed along an electron transfer chain, by embedded proteins. each time an electron moves it generates enough energy to transport a proton into intermembrane space. this results in an electrochemical gradient.
3) by facilitated diffusion the protons move down their electrochemical gradient, through ATP synthase, catalysing reaction of ADP+Pi-> ATP. this produces lots of ATP
4) oxygen picks up the hydrogen that has gone through ATP synthase and picks up electron at end of transfer chain an makes water with them.
