Biology Chapter 9 Flashcards
Glucose + Oxygen —> Carbon dioxide + Water + Energy
C6H12O6 + 6 O2 —> 6 CO2 + 6 H2O
Aerobic respiration
Uses oxygen
Anaerobic respiration
Does not use oxygen
Aerobic respiration is divided into 3 main stages
Glycolysis, Citric acid cycle, and Electron transport chain
Glycolysis
Glucose is split into 2 molecules of glyceraldehyde phosphate, then these are turned into pyruvate. This produces 2 ATP and 2 NADH.
Glucose
6 carbon atoms
Glyceraldehyde Phosphate
3 carbon atoms
Pyruvate
3 carbon atoms
Where does glycolysis take place?
The cytoplasm
Acetyl CoA
2 carbon atoms
Citrate
6 carbon atoms
Oxaloacetate
4 carbon atoms
Citric acid cycle (Krebs cycle)
The main chemicals are acetyl CoA, citrate, and oxaloacetate. This produces 2 ATP, 6 NADH, and 2 FADH2.
Takes place inside the mitochondria.
Produces the CO2 that we breath out.
Electron transport chain
Produces most of the energy (32 ATP molecules)
Converts the NADH and FADH2 into ATP.
Takes place in the mitochondria.
Energy produced in stages
Electron transport chain - 32 ATP molecules
Glycolysis - 2 ATP molecules
Citric acid style - 2 ATP molecules
The electron transport chain works as a proton pump
Pumps hydrogen ions (protons) through the membrane, and only allows them back through a protein (ATP synthase) which makes ATP.
Uses oxygen to accept electrons at the end of the chain (the electrons combine with hydrogen ions and oxygen to produce water molecules)
Glycolysis
Cytoplasm - breaks down glucose to pyruvate - 2 ATP - 2 NADH
Citric acid cycle
Mitochondria - turns pyruvate into CO2 -
2 ATP - 6 NADH - 2 FADH2
Electron transport chain
Mitochondria - converts NADH and FADH2 into ATP - 32 ATP
Catabolism of food
Cells can use several organic molecules in respiration, not just glucose. Carbohydrates are broken down using all 3 stages of respiration.
Catabolism of food
Lipids are broken down to glyceraldehyde, so they go through parts of glycolysis, then the citric acid cycle and the electron transport chain.
Catabolism of food
Proteins are deaminated (the amino group is removed) and then converted in acetyl CoA, which is used in his citric acid cycle, and then the electron transport chain (so they skip glycolysis)
Anaerobic respiration
Does not use oxygen
Only glycolysis can occur
Single called organisms (bacteria, yeast) can survive anaerobically.
Large animals (humans) build up on oxygen debt when anaerobic.
During anaerobic respiration, pyruvate builds up and is converted to
Lactate (lactic acid) in animals
Ethanol (alcohol) in plants
“Beer is proof that God loves us and wants us to be happy.”
Benjamin Franklin
Respiration
A catabolic reaction that breaks down glucose to release energy (ATP). Energy is stored in the cell as ATP or NADH.
