Nervous system 1 - divisions, neuroglia, neurons, hemisphere, and areas Flashcards
What are the main components of the Central Nervous System (CNS)?
The CNS includes the brain and spinal cord, responsible for integrating sensory information and responding accordingly.
What is the function of the Peripheral Nervous System (PNS)?
The PNS connects the CNS to the rest of the body, functioning as a communication network.
What are the two divisions of the PNS?
The Sensory division (transmits sensory information to the CNS) and the Motor division (transmits signals from the CNS to effector organs).
What are Neuroglia?
Supporting cells in the nervous system that provide protection, support, and maintenance for neurons.
What do Astrocytes do?
They maintain the blood-brain barrier, regulate electrical impulses, and clean excess neurotransmitters and potassium ions
What are the two divisions of the Autonomic nervous system?
The Sympathetic division (“fight or flight” response) and the Parasympathetic division (“rest and digest”).
What are the subcategories of the Motor division in the PNS?
The Somatic nervous system (voluntary control of skeletal muscles) and the Autonomic nervous system (involuntary regulation of visceral functions).
What are the main cells in the PNS?
Schwann cells and satellite cells
What are the key parts of a neuron?
Cell body, dendrites, axon, axon hillock, myelin sheath, node of Ranvier, terminal branches, and axonal terminals.
Name the types of Neuroglia in the CNS.
Astrocytes, Microglial cells, Ependymal cells, and Oligodendrocytes.
What is the role of Microglial cells?
They act as immune defenders in the CNS, transforming into macrophages to engulf pathogens and debris.
What is the function of Ependymal cells?
They line the ventricles of the brain and spinal cord, forming a barrier between cerebrospinal fluid and tissue fluid.
What is a Unipolar neuron (pseudo unipolar)?
one process extends from cell body and forms central and peripheral processes
- in PNS (common in dorsal root ganglia of spinal cords and sensory ganglia or cranial nerves)
What do Oligodendrocytes do?
They produce the myelin sheath in the CNS, which insulates nerve fibers and speeds up signal transmission.
What are the key parts of a neuron?
Cell body, dendrites, axon, axon hillock, myelin sheath, node of Ranvier, terminal branches, and axonal terminals.
What is the role of Schwann cells in PNS?
Schwann cells form myelin sheaths around peripheral nerve axons and help with nerve regeneration.
What is the function of Satellite cells in the PNS?
Satellite cells surround neuron cell bodies in ganglia, regulating the external chemical environment.
What is the difference between a nucleus and a ganglion?
A nucleus is a collection of neuron cell bodies in the CNS, while a ganglion is in the PNS.
What are Neurons?
Neurons are excitable cells responsible for transmitting electrical signals throughout the body.
What is the difference between a tract and a nerve?
A tract is a bundle of axons in the CNS, while a nerve is a bundle of axons in the PNS.
What are the three types of neurons based on the number of processes?
Multipolar, Bipolar, and Unipolar neurons.
What is a Multipolar neuron?
A neuron with many processes extending from the cell body
- common in the CNS.
What is a Bipolar neuron?
A neuron with two processes (cell body is aligned with axon)
- found in some sensory organs like the eye and ear.
What are the three functional regions of a neuron?
Receptive region (receives stimuli), Conducting region (transmits action potential), and Secretory region (releases neurotransmitters).