topic 7 pt 2

In vertebrate photoreceptors, Na⁺ channels _____ when light is absorbed.

• Channels open

• Channels close

• Channels remain unchanged

• Channels become inactive

The opening or closing of ion channels in mechanoreceptors is caused by _____

• Light absorption

• Chemical reactions

• Increased pressure

• Temperature changes

_____ is necessary for the perception of sensation in sensory neurons.

• Generation of action potential (AP)

• Presence of neurotransmitters

• Activation of ligand-gated channels

• Increase in temperature

If the receptor potential is not large enough to bring the cell to threshold, then _____

• An action potential will be generated

• The cell will depolarize

• No action potential will be generated

• The cell will hyperpolarize

The intensity of a sensory stimulus is coded by _____

• By the type of ion channels

• By the frequency of action potentials

• By the size of the receptor

• By the duration of the stimulus

The effect of light pressure on the firing rate is _____

• High firing rate

• No change in firing rate

• Low firing rate

• Variable firing rate

When intense pressure is applied to a membrane, it results in a _____.

• Slow influx of Na+

• Rapid influx of Na+

• No change in Na+ levels

• Decrease in Na+ levels

The role of hair cells in non-neural receptors is that they are _____ at rest.

• They secrete hormones

• They are polarized at rest

• They generate electrical impulses

• They absorb nutrients

_____ causes the release of neurotransmitters by receptors.

• Change in temperature

• Receptor potential

• Light exposure

• Sound waves

_____ are non-neural receptors.

• Muscle cells

• Epithelial cells

• Blood cells

• Bone cells