This document discusses cellular metabolism and energy production. It describes the two main types of metabolic pathways as catabolism, which breaks down molecules and releases energy, and anabolism, which builds molecules using energy. The goal of metabolism is to make ATP, which powers cellular reactions. Glucose undergoes glycolysis to produce pyruvate, which then enters the citric acid cycle in mitochondria. Electrons are transferred to generate NADH and FADH2, whose energy is used in the electron transport chain to power ATP synthesis through chemiosmosis. Glycolysis makes some ATP directly, while the citric acid cycle and electron transport chain make the majority of ATP from the energy in NADH and

1. ALTERING OF NUTRIENTS AND
METABLOISM
 SUBMITTED BY :- KIRAN
 B.Sc. BIOTECH
 6TH SEM
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2. METABOLISM
 Metabolism is the collection of
biochemical reactions that occur
within a cell, which includes a
tremendous diversity of molecular
conversions.
 Metabolic pathways can be
divided into two broad types :-
 Catabolism: The breakdown of
molecules into smaller units.
Energy is released in this
process.
Ex: Glucose catabolism results
in the release of CO2 and H2O
 Anabolism: The building of
compounds from small molecules
into larger ones. Energy is used
for this process to take place. 2

3. GOAL OF METABOLISM _MAKE
ATP
 Adenosine triphosphate, is referred to as
the “the energy of the cell” (cell energy)
because it powers most of the reactions that
take place in a cell.
 each ATP molecule has three parts:
 an adenine molecule
 a ribose molecule
 three phosphate molecules in a chain
 The ATP is the molecule that carries energy
to the place where the energy is needed.
When ATP breaks into ADP (Adenosine
diphosphate) and Pi (phosphate), the
breakdown of the last covalent link of
phosphate (a simple -PO4) liberates energy
that is used in reactions where it is needed.
 ATP ADP + P + energy 3

4. THE CAPTURE AND UTILIZATION OF ENERGY
 As the sole building block of CARBOHYDRATES that are broken down
during digestion and release energy .
 glucose is a key molecule in the energy metabolism of both plants and
animals. The free energy released by the complete oxidation of glucose is
very large .
 There are basically two stages in the catabolism of glucose, and they
are virtually identical in all aerobic organisms.
 The first stage glycolysis occurs in the soluble phase of the cytoplasm (the
cytosol) and leads to the formation of pyruvate.
 The second stage is the tricarboxylic acid (or TCA)cycle, which occurs
within the mitochondria of eukaryotic cells and the cytosol of prokaryotes
and leads to the final oxidation of the carbon atoms to carbon dioxide.
 Most of the chemical energy of glucose is stored in the form of high-
energy electrons, which are removed as substrate molecules are oxidized
during both glycolysis and the TCA cycle.
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5. GLYCOLYSIS
 Glycolysis is a series of reactions that and
extract energy from glucose by splitting it
into two three-carbon molecules called
pyruvates.
 Glycolysis – the first stage in cellular
respiration:-
 A series of enzyme catalyzed reactions.
 Glucose converted to pyruvic acid.
 Small number of ATPs made (2 per glucose
molecule), but it is possible in the absence
of oxygen.
 All living organisms use glycolysis.
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6. STEPS INVOLVE IN GLYCOLYSIS
 Event 1 – Phosphorylation
1) two phosphates added to
glucose
2) requires ATP
 Event 2 – Splitting (cleavage)
6-carbon glucose split into two 3-
carbon molecules
 Event 3 – Production of NADH
and ATP
1) hydrogen atoms are released
2) hydrogen atoms bind to NAD+
to produce NADH
3) NADH delivers hydrogen atoms
to electron transport chain if oxygen
is available
4) ADP is phosphorylated to
become ATP
5)two molecules of pyruvic acid
are produced 6

7.  Aerobic Reactions (Presence
of Oxygen)–
• Pyruvic acid is used to
produce acetyl CoA
• citric acid cycle begins
• electron transport chain
functions
• carbon dioxide and water are
formed
• 36 molecules of ATP
produced per glucose
molecule
 Anaerobic Reactions
(Absence of Oxygen) :-
• electron transport chain
cannot accept NADH
• pyruvic acid is converted to
lactic acid
• glycolysis is inhibited
• ATP production declines
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8. CITRIC ACID CYCLE
 The 3-carbon pyruvate loses a carbon
producing an acetyl group.
 Electrons are transferred to NAD+ forming
NADH.
 The acetyl group combines with CoA
forming Acetyl-CoA.
 Ready for use in Krebs cycle.
 begins when acetyl CoA combines with
oxaloacetic acid to produce citric acid
 citric acid is changed into oxaloacetic acid
through a series of reactions
 cycle repeats as long as pyruvic acid and
oxygen are available
 for each citric acid molecule:
 one ATP is produced
 eight hydrogen atoms are transferred to
NAD+ and FAD
 two CO2 produced
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10. ELECTRON TRANSPORT CHAIN (ETC)
 An electron transport chain (ETC) is a series of compounds that
transfer electrons from electron donors to electron acceptors via
redox (both reduction and oxidation occurring simultaneously)
reactions, and couples this electron transfer with the transfer of
protons (H+ ions) across a membrane.
 So far only 4 of the 38 ATP that will be produced have been, all by
substrate level phosphorylation.
 The remaining will be produced by the ETC.
 The majority of the ATP produced comes from the energy carried in
the electrons of NADH (and FADH2) that were produced by the
Krebs Cycle. 6 NADH and 2 FADH2
 The energy in these electrons is used in the ETC to power the
synthesis of ATP.
 There are thousands of ETC’s found in each mitochondria, which can
number in the 100’s depending on the cell type. 10

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12. PRODUCING ATP- CHEMIOSMOSIS
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13. REFERENCES
 Cell biology by karp
 https://www.slideshare.net/
 https://www.khanacademy.org/
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