Download Anaerobic Respiration

Section 3: Cellular Respiration
Living organisms obtain energy by breaking down organic
molecules during cellular respiration.
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9(B) Compare the reactants and products of photosynthesis and
cellular respiration in terms of energy and matter.
2(G) Analyze, evaluate, make inferences, and predict trends from data.
3(A) In all fields of science, analyze, evaluate, and critique scientific
explanations by using empirical evidence, logical reasoning, and
experimental and observational testing, including examining all sides of
scientific evidence of those scientific explanations, so as to encourage
critical thinking by the student.
4(A) Compare and contrast prokaryotic and eukaryotic cells.
4(B) Investigate and explain cellular processes, including homeostasis,
energy conversions, transport of molecules, and synthesis of new
molecules.
9(D) Analyze and evaluate the evidence regarding formation of simple
organic molecules and their organization into long complex molecules
having information such as the DNA molecule for self-replicating life.
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Cellular Respiration
Essential Questions
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What are the stages of cellular respiration?
What is the role of electron carriers in each stage of cellular respiration?
What are the similarities between alcoholic fermentation and lactic acid
fermentation?
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Cellular Respiration
Vocabulary
Review
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cyanobacterium
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anaerobic process
aerobic respiration
aerobic process
glycolysis
Krebs cycle
fermentation
Cellular Respiration
Overview of Cellular Respiration
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Organisms obtain energy in a process called cellular respiration.
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Respiration harvests electrons from organic molecules and uses the energy
to make ATP.
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The equation for cellular respiration is the opposite of the equation for
photosynthesis:
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Cellular Respiration
Overview of Cellular Respiration
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Cellular respiration occurs in two main parts: glycolysis and aerobic
respiration.
• Glycolysis is an anaerobic process, meaning it does not require oxygen.
• Aerobic respiration involves the Krebs cycle and electron transport.
• Aerobic processes require oxygen.
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Cellular Respiration
Glycolysis
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Glucose is broken down in the
cytoplasm through the process of
glycolysis.
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Two molecules of ATP and two
molecules of NADH are formed for
each molecule of glucose that is
broken down.
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Cellular Respiration
Krebs Cycle
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Glycolysis has a net result of two ATP and two pyruvate.
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Most of the energy from the glucose is still contained in the pyruvate.
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In the presence of oxygen, pyruvate is transported into the mitochondrial
matrix, where it is converted into carbon dioxide.
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The series of reactions in which pyruvate is broken down into carbon dioxide
is the Krebs cycle, also know as the tricarboxylic acid (TCA) cycle
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Cellular Respiration
Krebs Cycle
Steps of the Krebs cycle
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Prior to the Krebs cycle,
pyruvate reacts with coenzyme
A (CoA) to form acetyl CoA.
Acetyl CoA moves into the
mitochondrial matrix.
Acetyl CoA combines with a 4carbon compound to form citric
acid.
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Cellular Respiration
Krebs Cycle
Steps of the Krebs cycle
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Citric acid is broken down
releasing two molecules of
carbon dioxide and generating
one ATP, three NADH, and one
FADH2.
Finally, acetyl CoA and citric
acid are generated and the
cycle continues.
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Cellular Respiration
Krebs Cycle
Animation
FPO
Add link to concepts animation from page 230 (Figure 13) here.
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Cellular Respiration
Electron Transport
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In aerobic respiration, electron transport is the final step in the breakdown of
glucose.
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NADH and FADH2 from the Krebs cycle are used to convert ADP to ATP.
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Electron transport and chemiosmosis in aerobic respiration are similar to the
processes of photosynthesis.
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Cellular Respiration
Electron Transport
Prokaryotic cellular respiration
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Some prokaryotes undergo aerobic respiration.
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They do not have mitochondria, so they use the cellular membrane as the
location of electron transport.
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Cellular Respiration
Anaerobic Respiration
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When oxygen is unavailable, cells cannot follow glycolysis with the aerobic
respiration (Krebs cycle and electron transport).
The anaerobic process that follows glycolysis is anaerobic respiration, or
fermentation.
Fermentation occurs in the cytoplasm of the cell, and produces NAD+ and
ATP.
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Cellular Respiration
Anaerobic Respiration
Lactic acid fermentation
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Enzymes convert the pyruvate made during glycolysis into lactic acid.
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Skeletal muscles produce lactic acid when the body cannot supply enough
oxygen, such as during periods of strenuous exercise.
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Cellular Respiration
Anaerobic Respiration
Alcohol fermentation
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Occurs in yeast and some bacteria
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Converts pyruvate into ethyl alcohol and carbon dioxide
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Cellular Respiration
Photosynthesis and Cellular Respiration
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Cellular Respiration
Virtual Lab – Cellular Respiration
Concepts in Motion
FPO
Add link to concepts in motion interactive table from page 232 here.
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Cellular Respiration
BrainPOP – Photosynthesis & Cellular Respiration
Concepts in Motion
FPO
Add link to concepts in motion interactive table from page 233 here.
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Cellular Respiration
Review
Essential Questions
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What are the stages of cellular respiration?
What is the role of electron carriers in each stage of cellular respiration?
What are the similarities between alcoholic fermentation and lactic acid
fermentation?
Vocabulary
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anaerobic process
aerobic respiration
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aerobic process
glycolysis
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Krebs cycle
fermentation
Cellular Respiration