Plants respond to environmental stimuli like light and gravity through slow, hormone-driven growth adjustments, primarily controlled by auxins, to ensure survival and optimal resource acquisition.
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in today's video we're going to take a
look at how plants can respond to their environment
environment
and in particular we'll look at the role
now just like animals plants have to be
able to respond to stimuli in their
environment in order to survive
they just do it much more slowly than
animals do
for example they can sense light and
grow their shoots towards it to maximize photosynthesis
photosynthesis
they can sense gravity
so that they can grow their roots
downwards to fix themselves into the
soil and find more water and minerals
and some plants can even sense touch
so that they can climb around other objects
in order to do all of this stuff
plants have to rely entirely on hormones
they don't have any nervous system like
animals do
and the hormones that they do have
normally act locally
rather than flowing around the entire
organism like they would in animals
one group of these plant hormones are
the auxins
which control growth are the ends of the
shoots and the roots
once these organs are produced in the tips
tips
they then dissolve in the solution of
the cells
and diffuse backwards along the shoot or
the root
in the shoots these auxin stimulate growth
growth
causing the shoots to grow
but in their roots they do the opposite
the two responses we're gonna cover are phototropism
phototropism
which is a response to light
and geotropism which is a response to gravity
gravity
and you might also hear this be called gravitropism
