Patellar Reflex Mechanism and Functions

The video tutorial by Kevin Toh at Catalyst University explains the patellar reflex as a subtype of the stretch reflex. It details the anatomy and function of the reflex arc, including the roles of the quadriceps and hamstrings. The video also distinguishes between phasic and tonic reflexes and describes the pathway of the reflex arc, highlighting the sensory and motor neurons involved. The tutorial concludes with a preview of the next topic, the withdrawal reflex.

What is the patellar reflex primarily used to assess in a clinical setting?

• Neurological function

• Joint flexibility

• Bone density

• Muscle strength

Which type of reflex is characterized by being present only as long as the stimulus is applied?

• Dynamic reflex

• Phasic reflex

• Static reflex

• Tonic reflex

In the patellar reflex, which muscle group acts as the antagonist?

• Calf muscles

• Gluteal muscles

• Hamstrings

• Quadriceps

What is the primary role of muscle spindles in the patellar reflex?

• To provide energy to the muscle

• To relax the muscle

• To monitor muscle stretch

• To contract the muscle

What happens to the quadriceps when the patellar ligament is struck?

• They remain unchanged

• They elongate

• They contract

• They relax

Which neuron type is responsible for inhibiting the hamstrings during the patellar reflex?

• Sensory neuron

• Motor neuron

• Inhibitory interneuron

• Excitatory interneuron

What is the function of the inhibitory interneuron in the patellar reflex?

• To activate the sensory neuron

• To stimulate the spinal cord

• To inhibit the hamstrings

• To excite the quadriceps

Which part of the reflex arc directly excites the quadriceps motor neuron?

• Dorsal root ganglion

• Inhibitory interneuron

• Sensory neuron

• Motor neuron

What is the result of the patellar reflex when the quadriceps contract?

• Knee flexion

• Ankle dorsiflexion

• Hip rotation

• Knee extension

Which structure is struck to initiate the patellar reflex?

• Achilles tendon

• Patellar ligament

• Quadriceps tendon

• Hamstring tendon