what are gibberellins
a type of plant growth regulator involved in controlling seed germination and stem elongation
how does a Barley seed survive harsh conditions to germinate in good ones
in a state of dormancy as it contains very little water and is metabolically inactive
what does a barley seed contain
an embryo
an endosperm
an aleurone layer
what is the function of an embryo
will grow into the new plant when the seed germinates
what is an endosperm
a starch-containing energy store surrounding the embryo
what is an aleurone layer
a protein rich layer on the outer edge of the endosperm
what happens to a barley seed when the conditions are right
it starts to absorb water to begin the process of germination
beginning the process of germination stimulates
the embryo to produce gibberellins
what do gibberellins do once produced
diffuse into the aleurone layer and stimulate the cells there to synthesise amylase
how does gibberellin stimulate the synthesis of amylase
by regulating genes involved in the synthesis of amylase causing an increase in the transcription of mRNA coding for amylase
what is the function of the amylase synthesised by gibberellin
hydrolyses starch molecules in the endosperm producing soluble maltose molecules
what happened to the maltose produced
converted to glucose and transported to the embryo
what can the glucose eventually produced be used for
can be respired by the embryo to provide the energy needed to grow