True, all INSECTS have this.
You can tell the vein from the others by holding the leaf up to a light. This makes the leaf a bit see through and the veins will be clearly visible as they do not become semi-transperent. You can also put paper on top of the leaf and rub gently over the paper with crayon to see the veins. They will make darker or lighter lines on the paper depending on if you have the leaf facing up or down.
How_can_you_tell_the_vein_from_other_leaf_structures
The gap junction includes "micro tunnels" that are formed between two This junction it is an<span> intercellular connection that allows communication between cells and </span><span>exchange of ions, second messengers, and small metabolites between adjacent cells</span>
The micro tunnels are regulated gates through which this molecules pass.
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