Question

the simple patellar (pah - telar), or knee - jerk, reflex is an example of a two - neuron reflex arc, the simplest type in humans (figure 7 11b). the (1 ) reflex (in which the quadriceps muscle attached to the hit tendon is stretched) is familiar to most of us. it is usually tested during a physical exam to determine the general health of the motor portion of our nervous system. most reflexes are much more complex than the two - neuron reflex, involving synapses between one or more (2 ) in the cns (integration center). the flexor, or withdrawal, reflex is a three - neuron reflex arc in which the limb is withdrawn from a painful stimulus (see figure 7 11c). a three - neuron reflex arc also consists of five elements—receptor, sensory neuron, interneuron, motor neuron, and effector. because there is always a delay at synapses (it takes time for neurotransmitter to diffuse through the synaptic cleft), the more (3 ) there are in a reflex pathway, the longer the reflex takes to happen. many spinal reflexes involve only spinal cord neurons and occur without brain involvement. as long as the spinal cord is functional, spinal reflexes, such as the flexor reflex, will work. by contrast, some reflexes require that the (4 ) become involved because many different types of information have to be evaluated to arrive at the
ight\ response. the response of the pupils of the eyes to light is a reflex of this type. as noted earlier, reflex testing is an important tool in evaluating the condition of the nervous system. reflexes that are exaggerated, distorted, or absent indicate damage or disease in the nervous system. reflex changes often occur before a (5 ) condition becomes obvious in other ways. o 1 pathological 2 patellar 3 interneurons 4 synapses 5 brain o 1 brain 2 pathological 3 patellar 4 interneurons 5 synapses o 1 interneurons 2 synapses 3 brain 4 pathological 5 patellar o 1 patellar 2 interneurons 3 synapses 4 brain 5 pathological o 1 synapses 2 brain 3 pathological 4 patellar 5 interneurons

Explanation:

1. The simple patellar reflex is well - known and is tested in physical exams for the motor portion of the nervous system, so the first blank is 'patellar'.
2. More complex reflexes involve synapses between one or more interneurons in the CNS, so the second blank is 'interneurons'.
3. The more synapses in a reflex pathway, the longer the reflex takes due to neurotransmitter diffusion time at synapses, so the third blank is'synapses'.
4. Some reflexes require the brain to be involved when multiple types of information need evaluation, like the pupil - light reflex, so the fourth blank is 'brain'.
5. Abnormal reflexes can indicate a pathological condition before it becomes obvious in other ways, so the fifth blank is 'pathological'.

Answer:

1. patellar
2. interneurons
3. synapses
4. brain
5. pathological