Chapter 7 Human Physiology

Central Nervous System (CNS)

Comprises the brain and spinal cord.

Peripheral Nervous System (PNS)

Includes cranial nerves from the brain and 31 pairs of spinal nerves.

Neurons

Functional units of the nervous system that conduct electrical impulses and release chemical regulators.

Oligodendrocytes

Neuroglial cells that produce myelin in the CNS.

Microglia

Neuroglial cells that provide immune support in the brain.

Astrocytes

Neuroglial cells that maintain the blood-brain barrier and nutrient support.

Ependymal cells

Neuroglial cells that produce cerebrospinal fluid (CSF).

Schwann cells

Neuroglial cells that produce myelin in the PNS.

Satellite cells

Neuroglial cells that support neuronal health in the PNS.

Dendrites

Parts of neurons that receive information.

Cell Body

Part of neurons that processes information.

Axon

Part of neurons that conducts action potentials.

Axon Terminal

Part of neurons that relays information via neurotransmitters.

Nuclei

Clusters of similar neurons in the CNS.

Ganglia

Clusters of similar neurons in the PNS.

Sensory (Afferent) Neurons

Neurons that carry information into the CNS.

Motor (Efferent) Neurons

Neurons that transmit information away from the CNS.

Interneurons

Neurons that connect sensory and motor neurons within the CNS.

Nerve

A bundle of axons outside the CNS that can contain motor, sensory, or mixed fibers.

Myelin Sheath

An insulating layer formed by Schwann cells that increases action potential speed.

Nodes of Ranvier

Exposed gaps between myelin segments that facilitate quicker impulse transmission.

Depolarization

The process where the cell interior becomes less negative during action potential generation.

Repolarization

The restoration of resting potential after an action potential.

Hyperpolarization

The process where the cell interior becomes more negative.

Neurotransmission

The release of neurotransmitters influencing postsynaptic cells for neuron communication.

Acetylcholine (ACh)

A key neurotransmitter that can be excitatory or inhibitory.

Monoamines

Neurotransmitters, such as dopamine and norepinephrine, that modulate brain functions.

Synaptic Integration

The process where multiple signals converge to influence neuron activation.

Synaptic Plasticity

The ability of neural pathways to strengthen with repeated use, forming memories and adapting learning processes.

Long-Term Potentiation (LTP)

A key mechanism underpinning memory formation, characterized by lasting improvements in neuron communication.