Calvin cycle photosynthesis Video Lecture - NEET

[Music]
hello friends welcome to another video
tutorial from somos biology in the
series of videos we are talking about
plant photosynthesis and in the last two
videos we saw the overview of the
photosynthesis and what reactions are
present in the photosynthesis we have
also talked about light reactions of the
photosynthesis now in this video we want
to talk about the Calvin cycle of the
photosynthesis in details Calvin cycle
is also known as the dark reactions but
which is not kind of accurate thing to
say because the process of Calvin cycle
also occur in presence of light now what
happens in the calvin cycle we know that
the first step of the light reaction
provides them some material which will
be required to initiate the dark
reaction of the calvin cycle so the end
product of the light reactions are NADPH
ATP so we need both of them ATP provides
the source of the energy and NADPH acts
as an electron carrier which is also
required in different dehydrogenase
enzyme involved reactions different rate
of reactions because you know the
process of photosynthesis actually is a
type of endothermic rate of reaction so
here in the dark reaction what happens
the idea is only to fix carbon dioxide
we call it carbon fixation just like the
nitrogen fixation carbon dioxide
fixation is an idea it says that in the
plant cell there are five carbon
components so the carbon dioxide from
the air is combined to the five carbon
component that is present in the cell
itself and converting the five carbon
component into a six carbon component
but the six carbon intermediate is not
that stable so it will immediately split
into two three carbon components and
those three carbon components are the
first stable components of the process
of photosynthesis that is why we call
this pathway see
a three pathway of photosynthesis so
Calvin cycle in general mode known as a
c3 pathway and most of the plans that
you see nowadays living in the planet
actually following this cedhffi pathway
in this pathway the first stable
intermediate is produced and from that
intermediate continuously they help to
produce the glucose okay so what are the
exact stages of the directions of the
calvin cycle and how does this process
work to understand duck in more details
I will show you an animation so let's
focus on that animation in my computer
where I will explain each of the stages
involved with the specific enzyme for
the reaction okay so now in this video
we will see how the carbon fixation
takes place which is also known as c3
cycle or Kelvin cycle in the calvin
cycle to continue we need two materials
that are originated in the light
reactions of the photosynthesis one is
the ATP another one is the NADPH and we
also need a raw material that is carbon
dioxide to begin with because the idea
in the calvin cycle is to fix this
carbon from the carbon dioxide into a
chemical compound normally inside the
cell this is cyclic format of the
reactions that we generally produce
rather lows 1-5 bisphosphate inside the
cell of the plant so the regula fight
this phosphate can pair or bind to this
carbon dioxide and once carbon dioxide
gets fixed with the help of an enzyme
known as Rubisco or reviews bisphosphate
carboxylase oxygenase this enzyme can
fix carbon dioxide along with Reba
Lowe's 1:5 bisphosphate to convert it
into a six carbon component which is
kind of unstable and broken down into
two 3-carbon components known as c
phosphoglycerate so if we think the
process begins with three molecules of
regalos one five bisphosphate
and three molecules of carbon dioxide
so ultimately it gives us total 18
molecules of the carbon so at the end it
produces 3 phosphoglycerate and 6
molecules of 3 phosphoglycerate that
also gives us 18 carbon the best thing
that you need to do in all this process
of calvin cycle is to remember the
carbon calculations because you cannot
calculate it only with one molecule of
revellers 1 5 bisphosphate
it's difficult to calculate now once you
have 6 molecules of 3 phosphoglycerate
then the 3 phosphoglycerate is converted
into 1 3 bisphosphoglycerate and by
donating a phosphate group from ATP with
the help of phosphoglycerate kinase
enzyme so it will also produce 6
molecules of 1 3 bisphosphoglycerate
which is also 3 carbon molecule now this
1 3 bisphosphoglycerate is converted to
glyceraldehyde-3-phosphate by oxidizing
NADPH into an ATP here is the point
where they made the pH produced in the
light reaction is used and this process
is catalyzed by pivotal aldehyde 3
phosphate dehydrogenase enzyme so once
you produce glyceraldehyde 3-phosphate
then this glyceraldehyde 3-phosphate
there are 6 molecules of glyceraldehyde
3-phosphate produced in this process
among which one of the glyceraldehyde
3-phosphate molecule is only taken to
convert it into glucose any other types
of sugar so one out of six g3p is taken
to make sugar while five out of six is
taken to convert it into Robinho's one
five bisphosphate with the help of a
series of reaction that involves in the
phosphatase activity or removal of the
phosphate group as well as adding some
extra phosphate group which which
requires three molecules of ATP in the
stages but ultimately that converts five
molecules of glyceraldehyde 3-phosphate
into three molecules of Reb ulos one
five bisphosphate ultimately which both
leads to 15 carbon in calculations and
once we pretty
dribblers 1-5 bisphosphate then the
process of Calvin cycle can run again
through the same type of processes so as
you see the stages of the Calvin cycle
has not been difficult to remember but
the important step is the first one
involving the Rubisco and Rubisco is the
most abundant protein and enzyme that is
available in planet because it is
present in every single cell of the
organisms who are involved in the
process of photosynthesis and it is the
most important enzyme to fix the carbon
and without fixing carbon sugar cannot
be produced but the problem it will be
squeeze that Ruby school can utilize
carbon dioxide it can also utilize
oxygen so along with carbon dioxide if
it has access to oxygen it can also fix
oxygen and fixing oxygen is a waste of
energy for that reason sometimes
different plants choose a different
pathway rather than the c3 pathway to
nasty for pathway to complete the job of
photosynthesis we may call this video
for you to entertain as well as gain
some important knowledge about
fundamental processes like
photosynthesis so if you think this
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