Download Chapter 9 - SopoligaLake

Ch 9 In-Class Notes:
Cellular Respiration
1. The fundamental life processes of plants and
animals depend on a variety of chemical reactions
that occur in specialized areas of the organism’s
cells.
n
Heterotrophs are organisms that obtain
chemical energy by eating other organisms.
Ex: Animals, fungi, bacteria
n
n
The process that organisms must go through to
break down food for energy is called cellular
respiration.
(food à carbs, fats, proteins à ATP à energy)
Cellular respiration takes place in “mighty”
mitochondria.
n
n
n
n
All heterotrophs must ingest food that can be
converted into useable energy.
Reactants = Glucose and Oxygen
Products = Carbon dioxide, water, and ATP
Chemical Equation for Cellular Respiration:
C6H12O6 + 6 O2 à 6 CO2 + 6 H2O + ATP
n
n
n
All cells use chemical energy carried by the
molecule Adenosine Triphosphate (ATP).
ATP is one molecule of adenine bonded to three
phosphate groups by one ribose molecule.
Energy is released to be used by the cell when
the third phosphate bond breaks.
n
Glycolysis take place in the cytoplasm of a cell.
n
Glycolysis is the first step in cellular respiration.
n
Glycolysis results in 2 ATP molecules.
n
During glcolysis, one molecule of glucose is broken
down into two 3-Carbon molecules, called
pyruvate, or pyruvic acid.
n
n
The Krebs Cycle is the first main part of cellular
respiration that takes place in the mitochondrial
matrix.
The Krebs Cycle produces CO2 and 2 ATP
molecules from the products of glycolysis.
n
n
n
The Krebs Cycle also produces NADH and FADH2,
which are high-energy electron carriers.
The high-energy electrons are passed on to the
electron transport chain in the inner mitochondria
membrane.
The electron transport
chain produces about
30 - 35 ATP molecules.
n
n
n
n
An aerobic = not in air/without oxygen
If no Oxygen is present to allow proper cellular
respiration to occur, glycolysis is followed by
fermentation.
Fermentation occurs in the
cytoplasm.
Two types of fermentation
include alcoholic fermentation
and lactic acid fermentation.
n
n
n
When oxygen is absent, the products of glycolysis
may go through alcoholic fermentation.
Alcoholic fermentation produces carbon dioxide
and ethyl alcohol as waste products.
Alcoholic fermentation is very important in the
production of bread and many other valuable
commercial products.
n
n
n
When oxygen is absent, the products of glycolysis
may go through lactic acid fermentation.
Lactic acid fermentation produces lactic acid as
waste products.
Lactic acid fermentation is what causes your
muscles to hurt when you exercise them as fast
as you can.
n
n
Aerobic = with oxygen
When oxygen is present, the products of
glycolysis move into the mitochondria to go
through the final stages of cellular respiration.