Neural Control and Coordination – Key Vocabulary

Vocabulary flashcards covering essential terms from the lecture on neural control and coordination.

Coordination

Process by which two or more organs interact and complement each other’s functions to maintain homeostasis.

Homeostasis

Maintenance of a constant internal environment despite external changes.

Neural System

Network of specialised cells (neurons) that detects, receives, and transmits stimuli for rapid coordination.

Endocrine System

System of glands that provides chemical integration through hormones.

Neuron

Structural and functional unit of the neural system composed of a cell body, dendrites, and an axon.

Central Nervous System (CNS)

Brain and spinal cord; site of information processing and control.

Peripheral Nervous System (PNS)

All nerves associated with the CNS; connects CNS to the rest of the body.

Afferent Nerve Fibres

PNS fibres that carry impulses from tissues/organs to the CNS.

Efferent Nerve Fibres

PNS fibres that carry regulatory impulses from the CNS to peripheral tissues/organs.

Somatic Neural System

Division of PNS that relays impulses from CNS to skeletal muscles (voluntary control).

Autonomic Neural System

Division of PNS transmitting impulses from CNS to involuntary organs and smooth muscles.

Sympathetic Neural System

Part of autonomic system that generally prepares the body for ‘fight or flight’ responses.

Parasympathetic Neural System

Part of autonomic system that promotes ‘rest and digest’ activities.

Visceral Nervous System

PNS component consisting of nerves, ganglia, and plexuses connecting viscera with CNS.

Cell Body (Soma)

Neuron region containing cytoplasm, organelles, and Nissl’s granules.

Dendrites

Short, branching neuronal fibres with Nissl’s granules that carry impulses toward the cell body.

Axon

Long neuronal fibre that conducts impulses away from the cell body to synapses or neuromuscular junctions.

Nissl’s Granules

Rough endoplasmic reticulum and ribosome clusters in neuron cell bodies and dendrites; site of protein synthesis.

Synaptic Knob

Bulb-like terminal of an axon branch containing synaptic vesicles with neurotransmitters.

Neurotransmitter

Chemical messenger released at synapses to transmit nerve impulses across a gap.

Myelin Sheath

Insulating layer formed by Schwann cells around some axons; enables faster impulse conduction.

Node of Ranvier

Gap between adjacent myelin sheaths along a myelinated axon where ion exchange occurs.

Resting Potential

Electrical potential difference across the resting neuronal membrane due to ion gradients.

Sodium–Potassium Pump

Active transport protein that moves 3 Na⁺ out and 2 K⁺ into the neuron to maintain resting potential.

Action Potential

Rapid reversal of membrane polarity (depolarisation) that constitutes a nerve impulse.

Depolarisation

Process where Na⁺ influx makes the inside of the neuron positively charged relative to the outside.

Synapse

Junction between two neurons (or a neuron and another cell) where impulses are transmitted.

Electrical Synapse

Synapse with membranes in close proximity allowing direct current flow; faster, rare in humans.

Chemical Synapse

Synapse with a fluid-filled synaptic cleft where neurotransmitters mediate impulse transmission.

Synaptic Cleft

Narrow extracellular space separating pre- and post-synaptic membranes at a chemical synapse.

Cranial Meninges

Three protective brain coverings: dura mater (outer), arachnoid (middle), and pia mater (inner).

Forebrain

Anterior brain part including cerebrum; responsible for sensory processing, reasoning, memory, etc.

Midbrain

Central brain region involved in visual and auditory reflexes.

Hindbrain

Posterior brain part (pons, cerebellum, medulla) controlling balance and vital involuntary functions.