All vertebrates have general sensors in their skin for touch, pressure, and pain. these are called olfactory receptors chemoreceptors photoreceptors mechanoreceptors

The correct answer for the blank is -

mechanoreceptors.

Explanation:

Mechanoreceptors can be described as sensory receptors or cells preseng on skin or other organs , which respond to any mechanical stimuli like touch, difference in the pressure, sound etc.

These are the general sensors present in all vertebrates that are designed to sense touch, pressure, and pain.

mechanoreceptors

Explanation:

got this right on my assignment

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.