Nervous System - BIO103 student

Nervous System

Nervous System

The system in the body responsible for controlling our experience of the world, directing movements, consciousness, personality, learning, memory, and regulating homeostasis.

Sensory Nervous System

Detects stimuli and transmits information from receptors to the CNS.

Motor Nervous System

Initiates and transmits information from the CNS to effectors.

Neurons

Structural units that send and receive electrical signals and secrete neurotransmitters.

Resting Membrane Potential

The electrical charge across the plasma membrane of a neuron when it is not being stimulated.

Action Potential

Rapid change in membrane potential that allows neurons to transmit electrical signals.

Central Nervous System (CNS)

The part of the nervous system that includes the brain and spinal cord, responsible for receiving and processing information, initiating actions, and coordinating bodily functions.

Peripheral Nervous System (PNS)

The network of nerves outside the CNS that transmits signals between the CNS and the rest of the body, controlling voluntary and involuntary movements.

Brain

The organ in the CNS that receives sensory information, initiates responses, stores memories, generates thoughts and emotions.

Spinal Cord

Part of the CNS that conducts signals to and from the brain, controls reflex activities.

Motor Neurons

Neurons that carry signals from the CNS to control muscle and gland activities.

Sensory Neurons

Neurons that carry signals from sensory organs to the CNS.

Somatic Nervous System

Part of the PNS that controls voluntary movements by activating skeletal muscles.

Autonomic Nervous System

Part of the PNS that controls involuntary responses by influencing organs, glands, and smooth muscles.

Sympathetic Division

Part of the autonomic nervous system that prepares the body for stressful or energetic activities, known as the "fight or flight" response.

Parasympathetic Division

Part of the autonomic nervous system dominant during restful times, directing maintenance activities.

Information Processing

The process involving determining stimulus type, signaling intensity, integrating information, and initiating appropriate responses.

Reflex Arc

A simple behavior pathway where sensory stimulus leads to a predictable motor response.

Complex Behaviors

Actions requiring the convergence of multiple sensory inputs on interneurons to stimulate motor neurons for complex activities.

Cerebrum

The largest part of the brain responsible for higher mental functions, sensation, and movement.

Hyperpolarization

K+ diffusing out, makes inside more negative

Depolarization

More positive

Refractory Period

Temporary inactivation of Na+ channels

afferent neurons

carry sensory information from the body to the central nervous system, allowing us to perceive and respond to stimuli.

efferent neurons

neurons carry signals away from CNS to muscles and glands, allowing for motor functions and responses to stimuli.

interneurons

asociation signals between sensory neurons and motor neurons. They play a crucial role in processing information within the central nervous system.

neuroglia

supportive cells in the nervous system that provide structural support, insulation, and nutrients to neurons. They also play a role in immune defense.

Visceral

Part of Sensory NS input of internal organs and blood vessels

Somatic Sensory

Part of sSensory NS, sensory input of internal organs and blood vessels

Somatic motor

Motor NS, motor output to skeletal muscle

autonomic motor

Motor NS, cardiac, smooth, and glands

CNS, PNS

Motor moves from ___ to ___

PNS, CNS

sensory moves from to ___

dendrites

branch-like extensions of a neuron that receive signals from other neurons and transmit them to the cell body. They play a crucial role in communication within the nervous system.

cell body (soma)

the main part of a neuron that contains the nucleus and other organelles.

axon

long, slender projection of a nerve cell that conducts electrical impulses away from the cell body to other cells. It is covered by a myelin sheath which helps speed up the transmission of signals.

synaptic knob

axon terminal, at the end of a neuron's axon that releases neurotransmitters to communicate with other neurons or target cells.

synaptic cleft

the small gap between neurons where neurotransmitters are released to transmit signals.