| A rapid, automatic response to a stimulus, occurring without conscious thought. | Reflex Action |
| What is a reflex action? | A reflex action is a rapid, automatic response to a stimulus, occurring without conscious thought. |
| Reflex actions occur rapidly because they bypass the conscious part of the brain, eliminating the need for conscious thought. | Involvement of Conscious Brain |
| Why do reflex actions occur very quickly? | Reflex actions occur very quickly because they bypass the conscious part of the brain, eliminating the need for conscious thought. |
| Reflex actions, such as pulling away from something hot, help organisms avoid harm and prevent injury. | Protective Function of Reflex Actions |
| How do reflex actions help animals? | Reflex actions help animals avoid harm by allowing them to automatically respond to potential dangers, such as pulling away from something hot to prevent skin burns. |
| A specialized nerve pathway that mediates reflex actions, allowing rapid, involuntary responses to stimuli. | Reflex Arc |
| What is a reflex arc? | A reflex arc is a specialized nerve pathway that mediates reflex actions, allowing rapid, involuntary responses to stimuli. |
| The reflex arc begins when a receptor detects a stimulus, initiating a series of neural events. | Initiation of Reflex Arc |
| How does a reflex arc begin? | The reflex arc begins when a receptor detects a stimulus, initiating a series of neural events. |
| A nerve cell that transmits electrical impulses from a receptor to the central nervous system. | Sensory Neurone |
| What is the role of a sensory neurone in a reflex arc? | A sensory neurone transmits electrical impulses from a receptor to the central nervous system in a reflex arc. |
| A junction between two nerve cells, where electrical or chemical signals are transmitted. | Synapse |
| What happens at the synapse in a reflex arc? | Neurotransmitters cross the synapse, generating an impulse in a relay neurone. |
| A nerve cell that transmits impulses between sensory and motor neurones in the central nervous system. | Relay Neurone |
| What role does the relay neurone play in a reflex arc? | The relay neurone receives impulses from sensory neurones and transmits them to motor neurones, facilitating the reflex response. |
| A nerve cell that transmits impulses from the central nervous system to muscles or glands. | Motor Neurone |
| What is the function of the motor neurone in a reflex arc? | The motor neurone carries the impulse from the central nervous system to an effector, usually a muscle, initiating the reflex response. |
| A muscle or gland that responds to stimulation by contracting or secreting. | Effector |
| What is the effector's role in a reflex arc? | The effector, usually a muscle, responds to the impulse carried by the motor neurone by contracting, resulting in the reflex action. |
| A long, thin, tubular bundle of nervous tissue and support cells that extends from the brainstem to the lower back. | Spinal Cord |
| What role does the spinal cord play in a reflex arc? | The neurones in a reflex arc can pass through the spinal cord, facilitating rapid reflex responses without involving conscious thought. |
| The part of the brain responsible for automatic bodily functions and reflex actions, without conscious awareness. | Unconscious Brain |
| Where can the neurones in a reflex arc pass through besides the spinal cord? | The neurones in a reflex arc can also pass through the unconscious brain, facilitating reflex responses without conscious thought. |
