Scorpion venom has two active constituents: - a toxin that alters ion channels at synapses in the nervous system of their prey; - an inhibitor of an enzyme present at these synapses. For each constituent of the venom, suggest and explain one way in which it could prevent the synapse from functioning correctly.
State the function of a sensory receptor.
As a slit hair is bent by the movement of the sand the potential difference across the cell surface membranes of the slit hair cells becomes more positive inside compared with the outside. State the name given to the first change in potential difference that may lead to an action potential.
Action potentials may then be transmitted by the cells in the slit hairs to the central nervous system (CNS) of the scorpion. Explain how the scorpion is able to tell the difference between a small and a large movement of sand.