Study Notes
The nervous system in humans is responsible for coordinating and responding to stimuli through a network of neurons. It includes the central nervous system (CNS) and the peripheral nervous system (PNS), which work together to process information and trigger responses.
- Central Nervous System (CNS) — consists of the brain and spinal cord, controlling actions and responses. Example: The brain processes information and the spinal cord relays signals.
- Peripheral Nervous System (PNS) — includes all nerves outside the CNS, connecting it to limbs and organs. Example: Sensory neurons in the skin detect touch and send signals to the CNS.
- Neuron — a nerve cell that transmits electrical impulses. Example: Sensory neurons detect stimuli, relay neurons transmit signals within the CNS, and motor neurons carry signals to muscles.
- Synapse — the junction between two neurons where neurotransmitters are released to pass signals. Example: Neurotransmitters diffuse across the synaptic gap to continue the signal.
- Reflex Arc — a pathway that controls an involuntary response to a stimulus without involving the brain. Example: Pulling your hand away from a hot object without thinking.
Exam Tips
Key Definitions to Remember
- Central Nervous System (CNS)
- Peripheral Nervous System (PNS)
- Neuron
- Synapse
- Reflex Arc
Common Confusions
- Mixing up the roles of sensory, relay, and motor neurons
- Confusing the CNS with the PNS
Typical Exam Questions
- What is the first stage of mitosis? Prophase
- What is the term for when a cell divides? Cytokinesis
- Which type of neuron carries impulses from the CNS to effectors? Motor neuron
What Examiners Usually Test
- Understanding of neuron structure and function
- Ability to explain the process at a synapse
- Knowledge of reflex actions and their pathways