Metabolism and Survival Flashcards
What does Catabolic mean?
An energy releasing reaction that breaks down complex molecules to form simpler ones
What does anabolic mean?
A chemical reaction that uses energy to build up complex molecules from simple molecules
What is a phosphorylation reaction?
A phosphorylation reaction involves a phosphate group being added to a substrate. This is an enzyme controlled process. The formation of ATP from ADP and Pi is a phosphorylation reaction since a phosphate group is added to ADP to form ATP.
What is glycolysis?
It is the breakdown, in a series of enzyme-catalysed reactions, of the sugar glucose into two molecules called pyruvate.
Where does glycolysis take place?
The cytoplasm
Does glycolysis require oxygen?
No.
What is the net gain in ATP molecules during glycolysis?
2 ATP molecules
What is the first stage of glycolysis?
The energy investment stage, where 2 ATP molecules are needed to phosphorylate the intermediates.
What is the second stage of glycolysis?
The energy pay-off stage, 4 molecules of ATP are formed.
What are the products of glycolysis?
2 molecules of ATP, pyruvate, NADH
Where does the citric acid cycle occur?
The matrix of the mitochondria
What is stage 1 of the citric acid cycle?
During the citric acid cycle, pyruvate diffuses into the matrix of the mitochondrion, where it is broken down into an acetyl group. The acetyl group combines with coenzyme A forming acetyl coenzyme A (acetyl CoA). During the conversion of pyruvate to acetyl coenzyme A, dehydrogenase enzymes remove hydrogen ions and electrons from pyruvate which are passed to the coenzyme NAD, forming NADH.
What is stage 2 of the citric acid cycle?
The acetyl group from acetyl coenzyme A combines with oxaloacetate to form citrate. During the citric acid cycle, citrate is converted through a series of enzyme-catalysed reactions back into oxaloacetate. In the process, both carbon (in the form of carbon dioxide) and hydrogen ions (along with electrons) are released
What is stage 3 of the citric acid cycle?
Hydrogen ions and electrons become bound to NAD to form NADH. NADH will be used in the next stage of respiration to release energy for ATP production. Carbon dioxide diffuses out of the cell as a waste product and is expired from the organism by breathing out or by diffusion over the body surface.
Where is the electron transport chain?
On the surface of the Cristae (the folded inner membrane of the mitochondria)
