METABOLISM OF CELLS
Metabolism
• Metabolism refers to a series of chemical reactions that occur in a living organism to
sustain life.
• Primary metabolism comprises all metabolic pathways that are essential to the plant's
survival, generating compounds (metabolites) that are directly involved in the growth and
development of the organism.
• The chemical processes that occur in a cell.
• Reactions involve in synthesis or breakdown.
• Two kinds of chemical reactions occur in a cell’s metabolism.
Anabolic Reactions
• Also called as anabolism
• Chemical reactions in which energy is stored in molecules.
• Building-up process, large, complex molecules are synthesized from simpler
molecules.
• During photosynthesis, CO2 and H2O are used to synthesize carbohydrate
molecules such as glucose.
Catabolic Reactions
• Also called as catabolism
• Chemical reactions in which energy is released from molecules.
• Breaking-down process, large molecules are split apart, degraded into simpler
ones to release energy.
• The cellular respiration of glucose, glucose in broken down into CO2 and H2O
with the release of biologically useful energy.
REDOX (Oxidation-Reduction)
• The processing of energy by cells involves a transfer of energy through the flow of
electrons
• Characteristic of many cellular processes, including photosynthesis and cellular respiration
• A sequence takes place as electrons associated with hydrogen atoms are transferred from
one compound to another
, • Oxidation reaction is always accompanied by a reduction reaction because there are no
free electrons in living cells – all electrons are in atoms
• If a substance gains an electron in a reduction reaction, that electron must come from
another substance that has lost an electron
• As quickly as electrons are released, another atom or molecule accepts them
• At the same time as the oxidized molecule gives up electrons, it also gives up energy
associated with electrons; the reduced molecule receives energy when it gains electrons
Oxidation
• Chemical process in which a substance loses electrons
• Occurs when the oxidation state of a molecule, atom or ion is increased
• Involves the removal of hydrogen atom and its single electron from a compound
Reduction
• Chemical process in which a substance gains electrons
• Occurs when there is a gain of electrons or the oxidation state of an atom, molecule,
or ion decreases
• Involves a gain of a hydrogen atom and thus a gain in an electron
Photosynthesis
• For billions of years, almost all life in the
biosphere has run on solar energy.
• Of all organisms, however, only plants,
algae, and certain prokaryotes are capable
of absorbing and converting light energy
from the sun to chemical energy through
the process of photosynthesis
• The biological process that includes the
capture of light energy and its
transformation into chemical energy of organic molecules (such as glucose), which are
manufactured from carbon dioxide and water.
• The end products are carbohydrates and oxygen.
• Depends on visible light rather than some other wavelength of radiation.
• Chlorophyll, is not uniformly distributed in the cell but is confined to organelles called
chloroplasts.
• In plants, chlorophyll lies mainly inside the leaf in the cells of the mesophyll, a layer with
many air spaces and a high concentration of water vapor.
• The interior of the leaf exchanges gases with the outside through microscopic pores
called stomata. Each mesophyll cell has 20 to 100 chloroplasts.
• The chloroplast is enclosed by outer and inner membranes.
• The inner membrane encloses a fluid-filled region, the stroma, which contains most of the
enzymes required to produce carbohydrate molecules.
Metabolism
• Metabolism refers to a series of chemical reactions that occur in a living organism to
sustain life.
• Primary metabolism comprises all metabolic pathways that are essential to the plant's
survival, generating compounds (metabolites) that are directly involved in the growth and
development of the organism.
• The chemical processes that occur in a cell.
• Reactions involve in synthesis or breakdown.
• Two kinds of chemical reactions occur in a cell’s metabolism.
Anabolic Reactions
• Also called as anabolism
• Chemical reactions in which energy is stored in molecules.
• Building-up process, large, complex molecules are synthesized from simpler
molecules.
• During photosynthesis, CO2 and H2O are used to synthesize carbohydrate
molecules such as glucose.
Catabolic Reactions
• Also called as catabolism
• Chemical reactions in which energy is released from molecules.
• Breaking-down process, large molecules are split apart, degraded into simpler
ones to release energy.
• The cellular respiration of glucose, glucose in broken down into CO2 and H2O
with the release of biologically useful energy.
REDOX (Oxidation-Reduction)
• The processing of energy by cells involves a transfer of energy through the flow of
electrons
• Characteristic of many cellular processes, including photosynthesis and cellular respiration
• A sequence takes place as electrons associated with hydrogen atoms are transferred from
one compound to another
, • Oxidation reaction is always accompanied by a reduction reaction because there are no
free electrons in living cells – all electrons are in atoms
• If a substance gains an electron in a reduction reaction, that electron must come from
another substance that has lost an electron
• As quickly as electrons are released, another atom or molecule accepts them
• At the same time as the oxidized molecule gives up electrons, it also gives up energy
associated with electrons; the reduced molecule receives energy when it gains electrons
Oxidation
• Chemical process in which a substance loses electrons
• Occurs when the oxidation state of a molecule, atom or ion is increased
• Involves the removal of hydrogen atom and its single electron from a compound
Reduction
• Chemical process in which a substance gains electrons
• Occurs when there is a gain of electrons or the oxidation state of an atom, molecule,
or ion decreases
• Involves a gain of a hydrogen atom and thus a gain in an electron
Photosynthesis
• For billions of years, almost all life in the
biosphere has run on solar energy.
• Of all organisms, however, only plants,
algae, and certain prokaryotes are capable
of absorbing and converting light energy
from the sun to chemical energy through
the process of photosynthesis
• The biological process that includes the
capture of light energy and its
transformation into chemical energy of organic molecules (such as glucose), which are
manufactured from carbon dioxide and water.
• The end products are carbohydrates and oxygen.
• Depends on visible light rather than some other wavelength of radiation.
• Chlorophyll, is not uniformly distributed in the cell but is confined to organelles called
chloroplasts.
• In plants, chlorophyll lies mainly inside the leaf in the cells of the mesophyll, a layer with
many air spaces and a high concentration of water vapor.
• The interior of the leaf exchanges gases with the outside through microscopic pores
called stomata. Each mesophyll cell has 20 to 100 chloroplasts.
• The chloroplast is enclosed by outer and inner membranes.
• The inner membrane encloses a fluid-filled region, the stroma, which contains most of the
enzymes required to produce carbohydrate molecules.
