Lamina Shapes: Veins, Venation Video Lecture - NEET

hello friends this video on morphology
of flowering plants part 40 is brought
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from exam this I think I have covered
the of major basic parts of a leaf that
is lamina pitch whole leaf phase and the
steep chutes so now let us look at the
different types of leaves based on the
different lamina shapes so again now you
might be wondering how important is it
how important is the shape of the lamina
I mean what role does that play well
talking about the role which a shape
place obviously the shape of a leaf
helps in adapting to different types of
environment like you have some clams
with very thin own shaped leaves which
is good for those that kind of
environment where those lines are seen
so we really can say that the shape of a
leaf the shape of the lamina doesn't
play any role at all it definitely plays
a role so now here we will see what is
the different lamina shapes which are
seen in large so we will talk about two
things one is the merging of the lamina
that is the boundary of the naina and
the second thing would be the tip of the
lamina so basically we will talk about
these two things margin of the Lamb
behind tip of the lamina now where I
talk about the margin of the lamina that
is this boundary we have all these type
of shapes entire that means if you see
the margin on the boundary it is
complete there is no notches nowhere so
it is a it is known as entire the second
one is wavy so if you see the boundary
it is in the shape of a wave so that is
why it is called a wavy lamina not
slamming out so here you can see again
it is not neither entire nor those baby
but you can see
you actually see this whole kind of a
structure
so these notches are present so this is
called an launched laminar again if I
talk about the tip of a lamina that is
just this Epic's
so again we will see we have a variety
of shapes the first one is around so the
tip of the lamina this is the tip of the
lamina right the topmost portion so the
tip is round in shape when we say a cute
that means the tip is very pointed what
is action you would have studied about
acute angles and obtuse angle in your
geometry right so what does an actual
angle any angle which is less than 90
degrees now if you look at the tip of
this Eve what do you think this angle
will be this angle is a small and it'll
be less so this angle resembles actual
dangle and that is why it is given the
name of actual lamina of juice lamina
then this is not going to be very
pointed even though here if you see if
you look at this angle this angle looks
quite the arch right so it resembles to
some extent the obtuse angle and that is
why it is given the name of obtuse so
these are the different names which are
given to the different shapes of the
lamina depending upon the margin of the
leaf and the tip of the leaf so now
whenever you see up whenever you see any
plant you can actually define any why do
we give these names to different shapes
of Annie the let us suppose if I ask you
to describe the leaf of a plant now
there are so many varieties of branch
which exist on this earth so how will
you be able to this kind how distinct
believe on one plant is from the other
so for that you need some terminal logs
inside so now you have down the lodges
like this you can actually study how you
can actually observe a plant and you can
just tell that okay with it the this
plant so and so have a wavy you
and they have a mob juicy that means so
somebody will very clearly understand
that okay that means the margin of the
leave is in the shape of the wave and
the tip of the leaf is not very thin it
is it has an obtuse tip so anybody who
leaves that statement will be able to
visualize how that lis looks like right
so that that's how the terminal origins
are introducing the terminologies help
us to understand or absorb things better
so these are the different shapes of
lamina okay so now we will talk about
things but while I was talking about
lamina I told you that veins and
ringlets exist on the lamina so now let
us see what the veins and what function
do they perform veins are the vascular
tissues of views so they are very very
important so whenever I say vascular
tissues whatever Scalia tissues vascular
tissues are nothing but our side length
and flowing so veins are basically the
vascular bundles which contain xylem and
phloem talking about the function of
rains they help in transporting food
water and minerals as I told you I gave
you a comparison right of way the way
arteries and veins are there in our body
similarly veins and wavelets are there
in on the leaf so they actually have in
transporting food water and minerals to
different parts of the game because once
the food the food is absorbed food in
the same let us suppose whatever it is
food is prepared on this in the leaves
itself but I am saying water or
nutrients or whatever comes to the leaf
that needs to be distributed equally to
different corners of the knee so how
will that internal distribution within
the leaf a place that distribution
space with the help of these two blight
structures called veins and vagueness
they also provide rigidity to the leaf
blade now if you see these things they
are quite strong or quite rigid when
compared to the other portion of the
game and in this portion of the video if
you take a leaf
nd in your hand you will see that it
becomes very easy to tear the leaf from
here but it is not that easy to tear the
name from the vein because the veins are
little rigid so you need little you
needham give a little more pressure to
tear it from that portion right so has
there been no means of minutes the leaf
blade would have not at all been rigid
it would have been very thin and very
like it would have even if a little bit
of wind blows it would have actually got
damaged so these wings and green heads
also provide rigidity to the leaf blade
so again as you see both of them are
very important functions which are
performed by these things so now that we
are talking about the names it is very
very important that we talk about
variation this you ready we are talking
about Vee you all know that the function
of V the basic function of leaf is to
perform photosynthesis but when we talk
about leave indeed a we are going to
talk about the different shapes of
nature seen in plants how do we define
those shapes and I mean how are the
veins arranged energy we are going to
talk about the morphological to talk
about the external appearance of the
leaf from all aspects right ok so now
that I was talking about the games we
will talk about venation
what does variation here we will see how
greens are organized on how veins are
arranged on a leaf we will see that if
there are many different types of
arrangement of veins in different plants
are in different leaves
veins are arranged in different ways so
this will be interesting
so let us see what does my nation it is
the arrangement
vanes and the main gates in the lamina
of the obviously veins are present on
the leaf blade or lamina so how these
things are arranged that we will study
in miniature so there are some specific
patterns in which the wings are edged so
we will talk about the different types
of inertia now broadly there are two
types of variation that is reticulum
venation and family variation so these
are the two broad classification of
finishing so now we will see what is
reticule elimination and what is
parallel venation thank you please visit
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