Chapter 3_Cellular Anatomy of the Nervous System Flashcards
Extracellular space
The area outside of cells, filled with extracellular fluid that bathes and supports cells.
Cell membrane
Also known as the plasma membrane, it is the biological membrane that separates the interior of all cells from the outside environment.
Nucleus
The membrane-bound organelle in eukaryotic cells that contains the genetic material.
Intracellular space
The area inside a cell, containing the cytoplasm and organelles.
Lipid bilayer
The fundamental structure of the cell membrane, consisting of two layers of lipid molecules.
Phospholipid
A type of lipid molecule that is a major component of the cell membrane, with a hydrophilic head and hydrophobic tails.
Hydrophilic head
The part of a phospholipid that is attracted to water and faces the aqueous environments inside and outside the cell.
Hydrophobic tail
The part of a phospholipid that repels water and faces inward, away from the aqueous environments inside and outside the cell.
Proteins
Large, complex molecules that play many critical roles in the body, including catalyzing metabolic reactions, DNA replication, responding to stimuli, and transporting molecules.
Neuron
The basic working unit of the brain, a specialized cell designed to transmit information to other nerve cells, muscle, or gland cells.
Cytoplasm
The material within a cell, excluding the nucleus, containing organelles, cytoskeleton, and various particles.
Plasma membrane
Another term for the cell membrane, the boundary that separates the interior of the cell from its environment.
Phospholipid bilayer
The two-layer structure of the cell membrane, consisting of phospholipid molecules arranged with their hydrophobic tails inward and hydrophilic heads outward.
Membrane potential
The electrical potential difference across a cell’s membrane, resulting from the difference in ion concentrations inside and outside the cell.
Vm
The abbreviation for membrane potential, typically around -70 millivolts (mV) in neurons.
Neurogenesis
The process of generating new neurons, which occurs primarily during embryonic development but also in certain brain regions throughout life.
Plasticity
The ability of the brain to change its structure and function in response to experience or injury.
Dendrites
Branch-like extensions from the neuron cell body that receive signals from other neurons.
Spines
Tiny protrusions on dendrites that are sites of synaptic connections with other neurons.
Soma
The cell body of a neuron, containing the nucleus and much of the cytoplasm.
Axon
A long, thin projection of a neuron that conducts electrical impulses away from the neuron’s cell body.
Synapse
The junction between two neurons, where neurotransmitters are released to transmit signals from one neuron to another.
Astrocytes
Star-shaped glial cells in the brain and spinal cord, playing roles in supporting neurons and maintaining the blood-brain barrier.
Endfeet
Extensions of astrocytes that wrap around blood vessels in the brain, helping to maintain the blood-brain barrier.
Glutamate
A major excitatory neurotransmitter in the brain, involved in cognitive functions like learning and memory.
Tripartite synapse
A model of synaptic transmission that includes the presynaptic neuron, the postsynaptic neuron, and astrocytes.
Trophic factors
Molecules that support the growth, survival, and differentiation of neurons and other cells.
Camillo Golgi
An Italian physician and scientist known for developing the Golgi stain and advocating the reticular theory of the nervous system.
Golgi stain
A method of staining brain tissue that highlights individual neurons, developed by Camillo Golgi.
Reticular theory
An early hypothesis suggesting that the nervous system is a continuous network of interconnected cells.
Neuron doctrine
The theory that the nervous system is made up of discrete individual cells, known as neurons, a concept developed by Santiago Ramon y Cajal.
Santiago Ramon y Cajal
A Spanish neuroscientist who provided evidence for the neuron doctrine and made significant contributions to the understanding of the nervous system.
Nerves
Bundles of axons in the peripheral nervous system that transmit information to and from the brain and spinal cord.
Axon hillock
The cone-shaped region of an axon where it joins the cell body and where action potentials are initiated.
Axon terminal
The endpoint of an axon where neurotransmitters are stored and released.
Terminal bouton
The rounded ending of an axon terminal that makes synaptic contact with another cell.
Active zone
The area within the terminal bouton where synaptic vesicles release neurotransmitters into the synaptic cleft.
Microtubules
Cytoskeletal structures in neurons that help in the transport of organelles and vesicles within the cell.
Neurofilaments
Intermediate filaments in neurons that provide structural support and help maintain the shape of the cell.
Vesicles
Small membrane-bound sacs that transport and store neurotransmitters within the neuron.
Myelin sheath
A fatty layer that covers and insulates axons, speeding up the transmission of electrical impulses.
Nodes of Ranvier
Gaps in the myelin sheath along an axon where action potentials are regenerated.
Multiple sclerosis (MS)
A chronic disease characterized by damage to the myelin sheath, leading to disruptions in nerve signal transmission.
Unipolar neuron
A type of neuron with only one projection from the cell body, typically found in sensory neurons.
Bipolar neuron
A type of neuron with one axon and one dendrite extending from the cell body, commonly found in sensory systems like vision and olfaction.
Multipolar neuron
A type of neuron with one axon and multiple dendrites, the most common type of neuron in the central nervous system.
Sensory neurons
Neurons that carry information from sensory receptors to the central nervous system.
Motor neurons
Neurons that carry information from the central nervous system to muscles and glands.
Interneurons
Neurons that connect sensory and motor neurons and facilitate communication within the central nervous system.
Electron microscopy (EM)
A technique that uses a beam of electrons to create an image of a specimen, allowing for very high resolution and magnification.
Glia
Non-neuronal cells in the nervous system that provide support and protection for neurons.
Astrocytes
Star-shaped glial cells in the brain and spinal cord, playing roles in supporting neurons and maintaining the blood-brain barrier.
Glial fibrillary acidic protein (GFAP)
A protein expressed by astrocytes, used as a marker for astrocytes in research.
Oligodendrocytes
Glial cells in the central nervous system that produce the myelin sheath.
Schwann cells
Glial cells in the peripheral nervous system that produce the myelin sheath.
Microglia
Glial cells that act as the main immune defense in the central nervous system.
Ependymal cells
Glial cells that line the ventricles of the brain and the central canal of the spinal cord, involved in the production and circulation of cerebrospinal fluid.
