The following are the steps involved in a neural reflex.

1. Activation of a sensory neuron

2. Activation of a motor neuron

3. Response by an effector

4. Arrival of a stimulus and activation of a receptor

5. Information processing

The proper sequence of these steps is

(a) 1, 3, 4, 5, 2

(b) 4, 5, 3, 1, 2

(c) 4, 1, 5, 2, 3

(d) 4, 3, 1, 5, 2

(e) 3, 1, 4, 5, 2

What are the components of a visceral reflex arc?

The reflexes that control the most rapid, stereotyped motor responses to stimuli are

(a) Monosynaptic reflexes

(b) Polysynaptic reflexes

(c) Tendon reflexes

(d) Extensor reflexes

The contraction of flexor muscles and the relaxation of extensor muscles illustrate the principle of

(a) Reverberating circuitry

(b) Generalized facilitation

(c) Reciprocal inhibition

(d) Reinforcement

Reflex arcs in which the sensory stimulus and the motor response occur on the same side of the body are:

(a) Contralateral

(b) Paraesthetic

c) Ipsilateral

(d) Monosynaptic.

List, in sequence, the five steps involved in a neural reflex.

Polysynaptic reflexes can produce far more complicated responses than can monosynaptic reflexes because

(a) The response time is quicker.

(b) The response is initiated by highly sensitive receptors.

(c) Motor neurons carry impulses at a faster rate than do sensory neurons.

(d) The interneurons involved can control several muscle groups.

What five characteristics are common to all polysynaptic reflexes?

What effect does the stimulation of a sensory neuron that innervates an intrafusal muscle fiber have on muscle tone?

Bowel and urinary bladder control involve spinal reflex arcs that are located in the sacral region of the spinal cord. In both instances, two sphincter muscles—an inner sphincter of smooth muscle and an outer sphincter of skeletal muscle—control the passage of wastes (feces and urine) out of the body. How would a transection of the spinal cord at the L₁ segment level affect an individual's bowel and bladder control?