Mechanisms of Plant Electrophysiology - Electro-Horticulture - page 71

the flow of information within the plant's entire body and beyond 6 . It uses these signals
to respond to sources of internal and external stimuli which can range from the detection
of chemical compounds in the soil such as root exudates 7 , to the activation of various
hormones or genes which could tell the plant to initiate certain behaviors. For instance,
hormones could be activated in response to stressors such as insect attack, where the
production of “insect repellent” chemical compounds would be synthesized. Under normal
conditions this reaction may occur, but under stimulation, reports so far indicate that plants
begin to take actions for actively repelling insects, perhaps through the amplifying the
original responses.
Electricity in Biology
In this day and age it's common knowledge that both humans and animals are electrical
in nature. Part of the reason this is universally known is because of the progress made in
the biomedical engineering community. Through their efforts, devices are now commonly
found within the medical community like electrocardiograms (ECGs) and
electroencephalograms (EEGs) 8 . Weknowthatevenfishandinsectsareelectrical. Electric
eels are capable of delivering electric shocks to subdue other fish, and fireflies
electrochemically blink on and off in the early evenings of summer. Even with this
knowledge, how often do we think of plants as electrical, too?
Because of many of the same mechanisms that exist in mammals, fish, and insects, plants
are also electrical in nature. How is that so? What these two different forms of life have in
common aretheir cell-based makeup. Cells areelectrical bytheir verynature duetoawide
range of complex interactions that occur between electrically-charged atoms, molecules,
proteins and other structures. These interactions can be described using concepts from cell
biology and electro-chemistry.
Unstableatoms 9 , calledions,areconstantlyflowingintoandoutofcellsduetotheconstant
stateofchangethatoccursinside,outsideandbetweencells.Thisflowofionscanbefound
traversing the fluids that surround cells (known as extracellular fluid) and the fluids inside
the cell (known as the cytoplasm) via the cell's outer membrane as well as the different
organs and structures found within it. The ebb and flow of ionic uptake, processing and
release that occur in response to the happenings within and around all cells, causes an
unequal distribution of ions 10 across the cell's plasma membrane, forming one of the
mechanisms that creates electric fields in basic cell biology.