Download 9.1 Cellular Respiration

Cellular Respiration
8.1 Overview
What is respiration?
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Three definitions
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Inspiration-expiration
Exchange of O2 for CO2 in lungs
Consumption of O2 and production of CO2 in tissues
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Involves glucose
Exergonic
Produces ATP
Redox reaction
What are NAD+ and FAD?
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
Enzymes use these
during oxidation
respiration
FAD sometimes used
instead
What are the phases of respiration?
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Glycolysis
Krebs cycle (citric acid cycle)
Electron transport chain
Cellular Respiration
8.2 Glycolysis
What is glycolysis?
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Literally means _________
Happens outside mitochondrion
Goal is to generate pyruvate
Two stages
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Energy investment
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Phosphoryation using 2 ATP
Energy harvest

See next slide…
What happens during energy harvest?
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Substrate level phosphorylization
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To make ATP
Pyruvate also formed
Overall reaction:
Cellular Respiration
8.3 Krebs Cycle
What is the Krebs Cycle?
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AKA the citric acid
cycle
Happens in
mitochondrial
matrix
Goal: generate ATP,
FADH2 and NADH
from pyruvate
Series of redox
reactions

A type of
metabolic pathway
What are the steps?
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Prepatory step
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Convert pyruvate to acetyle co-A
What happens next?
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Citric Acid Cycle
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Key: it’s a cycle– it repeats!
What are the products of the Krebs cycle?
Cellular Respiration
8.4 Electron transport chain
What is the electron transport chain (ETC)?
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Series of redox
reactions to make
______
Happens in cristae
Oxidative
phophorylation
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Consumes oxygen
Produces ATP +
H 2O
What are the steps of the ETC?
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Chemiosmosis involved
Passing of
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Electrons
H+
What is energy yield of oxidative respiration?
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After all three stages
Cellular Respiration
8.5 Fermentation
What happens if no oxygen is present?
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Anaerobic respiration
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Fermentation
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Inorganic molecule is final electron acceptor
Some bacteria use
Organic molecule is final electron acceptor
Different types
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Alcoholic fermentation
Lactic acid fermentation
What happens in fermentation?
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Glycolysis
Then
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pyruvate
reduction
NAD
regeneration
What are the pros and cons of fermentation?
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Pros
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Oxygen not necessary
Cons
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Very low ATP production
What is the metabolic pool?
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Compounds oxidized
for entry into
biosynthesis
reactions
Catabolism
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Deamination (in
liver)
Anabolism