GLYCOLYSIS Flashcards
Cellular respiration consists of-
Multiple, controlled, sequential, enzymatic reactions
-This enables your cells to gradually release and capture more useful energy from a glucose molecule
Each glucose molecule →
More ATP
The efficiency of cellular respiration:
Varies slightly among human cell types, tissues, organs
The catabolism of one glucose molecule by cellular respiration yields _____ ATP molecules
~30-38 ATP
-Efficiency is ~35-40% (the amount of released energy used to make ATP)
Glycolysis
-Sugar splitting
-The catabolic process that begins to release energy from glucose molecules
What enzyme splits the 6 carbon glucose molecule into 2, 3 carbon molecules during glycolysis
Aldolase
Glycolysis is an-
Ancient catabolic pathway
-It may predate cells
-A pathway is a sequence of connected chemical reactions that perform a specific cellular function
Glycolysis consists of:
-10 sequential enzymatic reactions in the cytosol
After cells import ____ molecules, they can immediately enter glycolysis
Glucose
The _____ of the 1st glycolytic enzyme becomes the _____ for the second enzyme etc
Product → substrate
Energy investment phase reactions
-Require ATP molecules
-Hexokinase & PFK perform these reactions (consumes 2 ATP)
-Each enzyme requires ATP as a substrate
-Each enzyme adds a PO4 group from ATP to the 6 carbon carbohydrate
Phosphorylation
-Retains glucose in the cell
-Enables the import of glucose into the cytosol by facilitated diffusion
Energy payoff phase reactions
-Produce 3 types of energy rich molecules
The catabolism of 1 glucose molecule by the energy payoff phase reactions produces-
-4 ATP molecules (the energy investment reactions consume 2 ATP, so the net gain is 2 ATP)
-2 NADH molecules
-2 pyruvate molecules
Phosphoglycerokinase & Pyruvate Kinase make ATP by:
Substrate level phosphorylation
-The active site directly transfers a PO4 group from the carbohydrate substrate to ADP to make ATP
