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7th Grade Life Science
Mr. Fisk
Chapter 3 – Chemical Compounds in Cells
Engage – Count the number of times you breath in
1 minute.
Objectives:
1. Describe the events that occur during
respiration.
2. Tell what fermentation is.
3-4 - Respiration
A. What is Respiration?
1. Respiration – process by which cells obtain
energy from glucose.
 Sugar → Energy
2. Storing and Releasing Energy.
 Cells store food – like money in a savings
account.
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7th Grade Life Science
Mr. Fisk
3. Breathing and Respiration .
 Breathing – moving air in and out of your
lungs.
 Respiration – occurs in cells.
4. 2 Stages of Respiration
 Stage 1 – occurs in the Cytoplasm –
glucose molecules broken down into
smaller molecules.
 Stage 2 – occurs in the Mitochondria –
glucose combine with O2 to produce
Energy.
5. Respiration Equation
C6H12O6 + 6O2
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→6CO2 + 6H2O + Energy
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7th Grade Life Science
Mr. Fisk
6. Comparing Photosynthesis and
Respiration
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7th Grade Life Science
Mr. Fisk
B. Fermentation .
1. Fermentation – energy releasing process
that does not require O2.
 Single – celled organism deep in the
ocean or in the mud of lakes etc.
 1 molecule of glucose produces much
less energy.
2. Alcoholic Fermentation
 Yeast break down sugar
 Alcoholic – Produce
 Glucose→ Alcohol + ATP + CO2
3. Lactic Acid Fermentation
 Oxygen debt situation – running up a hill
etc. – body cannot get enough oxygen.
 Glucose → Lactic Acid + ATP = CO2
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