RESPIRATION IN PLANTS - Video Lecture Video Lecture - Class 11

respiration implants respiration and its
initial steps the breaking of carbon
bonds of complex compounds through
oxidation within the cell leading to
release of considerable amount of energy
is called respiration both aerobic and
anaerobic types of respiration have a
common series of initial steps termed
glycolysis during glycolysis
carbohydrates are converted into pyruvic
acid the pyruvic acid thus formed enters
the mitochondria where oxygen and
necessary enzymes are available the
pyruvic acid is finally converted into
carbon dioxide and water the sequence of
events constitutes the Krebs cycle the
overall events of respiration are shown
in these schematic representations
glycolysis glycolysis is common pathway
for both aerobic and anaerobic modes of
respiration in this process glucose
undergoes partial oxidation to form two
molecules of pyruvic acid the entire
process of glycolysis occurs in the
cytoplasm of the cell
note the various intermediate reactions
which lead to the conversion of glucose
to two molecules of pyruvic acid in the
summarized representation
Krebs cycle krebs cycle was first
elucidated by a British by chemist Sir
Hans Krebs in the year 1937 aerobic
respiration takes place within the
mitochondria pyruvate which is formed by
the glycolytic catabolism of
carbohydrates in the cytosol undergoes
oxidative decarboxylation by a complex
set of cyclic reactions at the end of
Krebs cycle we get 8 molecules of NADH +
H+ two molecules of fadh2 and two
molecules of ATP
difference between aerobic and anaerobic
respiration the oxidative breakdown of
respiratory substrates with the help of
atmospheric oxygen is known as aerobic
respiration whereas oxidation of
respiratory substrates in the absence of
atmospheric oxygen is known as in
aerobic respiration the differences
between aerobic and anaerobic
respiration is tabulated here
the electron transport system the
metabolic pathway through which the
electron passes from one carrier to
another is called the electron transport
system as represented in the diagram
this is the last step of aerobic
respiration in which oxidation of
reduced coenzymes namely NADH + H+ and
fadh2 formed during glycolysis and Krebs
cycle takes place through the electron
transport system oxidation of one
molecule of NADH gives three molecules
of ATP while oxidation of one molecule
of fadh2 produces two molecules of ATP
interrelationships among metabolic
pathways the respiratory pathway is an
amphib Baalak pathway as it involves
both anabolism and catabolism all along
the respiratory process there is a
breakdown of substrates and synthesis of
substrates note the interrelationships
among metabolic pathways shown in the
schematic representation and the
breakdown of respiratory substrates to
form carbon dioxide and water