Short-Term Lactic Acid glycolysis Short-Term Lactic Acid

Learning goals We are learning to understand the role of glycolysis in energy production. We are learning to explain the steps involved in glycolysis. We are learning to discuss the activities requiring this pathway.

ATP resynthesis from partial GLUCOSE breakdown glycolysis used to transition from anaerobic to aerobic energy production 10 sec - 2 min results in the partial breakdown of glucose (via glycogen stores in muscle) it's relatively fast, because it’s relatively simple (10 steps): ATP resynthesis from partial GLUCOSE breakdown

Activities! 400m run 800m run hockey shift swimming sprints

allows for longer burst of E! (but produces lactic acid)

Let’s draw it!!

For your viewing pleasure Glycolysis: An Overview

Energy investment phase Starts with: 1 glucose molecule (C6H12O6) an ATP is hydrolyzed in order to add an additional phosphate group to the glucose molecule (glucose-6-phosphate) the glucose molecule is converted into a fructose molecule (simply an isomer of glucose) (fructose-6-phosphate) another ATP is hydrolyzed to add a 2nd phosphate group (fructose-1-6- biphosphate) 4. & 5. glucose molecule is split into two 3-carbon molecules (glyceraldehyde-3-phosphate)

Energy generation phase In the remaining 5 reactions, each G-3-P is converted into a pyruvate (3 carbons each) and: 2 ATP produced 2 Hydrogen (H+) ions are removed and ‘picked up’ by the carrier molecule NAD+ (which becomes NADH+H) If oxygen is available, the 2 pyruvates move on to the AEROBIC ENERGY SYSTEM If oxygen is NOT available, the 2 pyruvates become LACTIC ACID = ouch!! (both of these carry the E! that was in the bonds of the glucose)

unless there is no oxygen available (i. e unless there is no oxygen available (i.e., you’re working at your max)...in that case, pyruvate has to accept the H+ ions (instead of NAD which is still busy in aerobic cycle)

Pyruvate vs. lactic acid if oxygen is available (i.e., during sub-maximal workout): NAD accepts the H+ ions that are removed from G3P (on its way to becoming pyruvate) NADH+H ‘carries’ the H+ ions and drops them off at the mitochondria for use during AEROBIC RESPIRATION

if oxygen is NOT available (i.e., during maximal workout): AEROBIC respiration can’t happen, so NADH+H can’t drop off its H+ ions (i.e., it gets stuck waiting at the mitochondria) thus, pyruvate has to take the H+ ions back from NADH+H (or they’ll build up and stop glycolysis = no E!) and becomes lactic acid the point at which this lactic acid build up is called the ANAEROBIC THRESHOLD (i.e., burning sensation)

“CLUB MITO”

NET PRODUCTS PYRUVATE ATP NADH+H 2

ATP-PC GLYCOLYSIS Location Energy Source Oxygen Required? # of ATP Produced Duration # of Rxns Involved Limitation Advantage Types of Exercise

Learning goals We are learning to understand the role of glycolysis in energy production. We are learning to explain the steps involved in glycolysis. We are learning to discuss the activities requiring this pathway.

Glycolysis review questions What type of activities would use Glycolysis to produce ATP? Where does Glycolysis take place? How many reactions are in Glycolysis? What are the products of this pathway? Is this pathway aerobic or anaerobic? How is this pathway connected to the aerobic pathway? What is the role of NAD? What is lactic acid? Why is it created? How do we get rid of it? What is NADH and what is its role?