100 likes | 734 Views
Reflex Arcs. Nerve impulse pathways that are responsible for involuntary actions Look like the pathway you drew and labeled: Receptor to Sensory neuron to (optional step) Interneurons in the CNS (a reflex center) to Motor neurons to Effector. Reflexes.
E N D
Reflex Arcs • Nerve impulse pathways that are responsible for involuntary actions • Look like the pathway you drew and labeled: • Receptor to • Sensory neuron to • (optional step) Interneurons in the CNS (a reflex center) to • Motor neurons to • Effector
Reflexes • Automatic subconscious responses to changes within or outside the body: • Maintain homoestasis: blood pressure, heart rate, respirations, digestion, temperature • Automatic actions: swallowing, coughing, sneezing, vomiting
2 Examples of Types of Reflexes (?) • Knee-jerk reflex (patellar tendon reflex) • Employs only 2 neurons: sensory neuron communicating directly with a motor neuron • Withdrawal reflex: • A response to painful stimuli • Sensory neuron takes impulse to interneurons in the spinal cord reflex center, where it is transmitted to motor neurons. • Other interneurons carry impulses to the brain for processing of the experience and pain.