Chptr 29 Sensory

You arrive at your office and are startled by the sounds of building construction outside your window. As you settle into your work for the day, you forget about the construction noises. When a visitor comes to your office later that day, the first thing she comments on is how disruptive the construction noise must be to your concentration. You realize that you have not even noticed it for over an hour. This is due to _.

• Sensory transduction.

• Sensory adaptation.

• Action potential firing.

• None of them.

Suppose you have three water baths in front of you. The temperature of the one on the left is 22°C (cold), the one in the middle is 25°C (room temperature), and the one on the right is 44°C (warm). At the same time, you place the index finger of your right hand into the warm water bath and the index finger of your left hand into the cold water bath, and you leave them there for 2 minutes. After 2 minutes, why would you no longer feel a difference in temperature between the two water baths?

• The sensory receptors in your index fingers speed up the conversion of the stimulus (water) to a chemical signal.

• The sensory receptors in your index fingers diminish the conversion of the stimulus (water) to an electrical signal.

• The sensory receptors in your index fingers become less sensitive over time as they are stimulated repeatedly.

• Receptor potentials in the sensory receptors in your index fingers start off weak and then become stronger.

Sensory transduction occurs in the _.

• Cerebral cortex of the brain.

• Stimulus of the environment.

• Spinal cord of the nervous system.

• Plasma membrane of sensory cells.

In stimulus detection, sensory receptor cells convert a stimulus into a(n) _.

• Neurotransmitter.

• Enzyme.

• Electric signal.

• Astigmatism.

The receptor potential is the _.

• Membrane potential produced when a neurotransmitter molecule binds to its receptor.

• Membrane potential produced in the receptor cell by sensory transduction.

• Electrical signal produced by an action potential.

• Membrane potential produced at a muscle cell.

What is an example of sensory adaptation of receptors?

• Distinguishing between different colors.

• Ignoring the shoes on your feet.

• Thinking about what you would do with a million dollars.

• Detecting sound and light simultaneously.

Which statement best describes the basis of sensory adaptation?

• A continuously stimulated sensory receptor triggers fewer action potentials, so stimuli sent to the brain decrease and awareness of the stimuli is diminished.

• The nerve fiber synapsed with a sensory receptor gradually returns to its baseline level of firing despite continued neurotransmitter stimulation.

• The spinal cord interneurons that receive a prolonged stimulus gradually come to ignore it.

• The thalamic centers that receive a prolonged stimulus gradually come to ignore it.

Which class of sensory receptors responds to stimuli such as touch, pressure, stretching, and sound?

• Thermoreceptors.

• Mechanoreceptors.

• Electromagnetic receptors.

• Chemoreceptors.

Which type of sensory receptors becomes more sensitive when damaged tissues produce prostaglandins?

• Deep pressure receptors.

• Photoreceptors.

• Pain receptors.

• Temperature receptors.

Which receptor transduces when it changes shape and its plasma membrane becomes more permeable to sodium or potassium ions?

• Pain receptor.

• Thermoreceptor.

• Mechanoreceptor.

• Chemoreceptor.