Respiration Flashcards
Where glycolysis fits in the overall process of respiration
-Glycolysis is the first stage of aerobic and anaerobic respiration
-occurs in cytoplasm of the cell
Process of glycolysis
1) glucose converted into phosphorylated glucose by hydrolysis of 2x ATP molecules to ADP (provides energy to activate glucose
and lowers AE for enzyme controlled reactions that follow)
2) Phosphorylated glucose split into 2X triose phosphate (3C molecule)
each triose phosphate oxidised (H removed from each of 2 triose phosphate and transferred to H carrier molecule AKA NAD > NADH
3) enzyme controlled reactions convert each triose phosphate into another 3C molecule (pyruvate) so 2 molecules of ATP are regenerated from ADP
Where does glycolysis occur?
cytoplasm
What is glycolysis involved in?
aerobic AND anaerobic respiration
What are the end products of glycolysis?
-net gain of 2 x ATP
-2 x reduced NAD (NADH)
-2 x pyruvate
How many ATP are hydrolysed for the phosphorylation of glucose?
2
Why does glucose phosphate split?
it is unstable
For 1 GLUCOSE molecule, how many ATP are produced (in the oxidation of triose phosphate(s))
4 (2 per TRIOSE PHOSPHATE)
What is NAD converted into in the oxidation of triose phosphate to form pyruvate?
NADH (2 per GLUCOSE)
How many pyruvate are made for each glucose molecule?
2
What is produced in glycolysis and is needed in the next stages of respiration?
-NADH
-PYRUVATE
How are pyruvate and NADH transported into the mitochondrial matrix?
active transport
Process of link reaction
-pyruvate molecule from glycolysis diffuses from cytoplasm across mitochondrial membrane into mitochondrial matrix
-pyruvate (3c) is oxidised (and decarboxylated) to acetate (2c molecule) so CO2 is produced as a by-product and the 2H lost from pyruvate is accepted by NAD>NADH to be used in ATP later on (in anaerobic resp)
-acetate combined with coenzyme A (CoA) to produce acetyl coenzyme A (2c molecule)
Why does links reaction happen
so pyruvate from glycolysis can be oxidised first before entering kerbs cycle
What reaction makes acetate?
the oxidation of pyruvate