Lesson 25.1 - An Overview of the Nervous System Flashcards
It is the network of nerve cells and fibers which transmits nerve impulses between parts of the body.
The Nervous System
The Nervous System
It is the network of nerve cells and fibers which transmits nerve impulses between parts of the body.
What are the two major parts of the nervous system?
Central nervous system
Peripheral nervous system
It is composed of the brain and the spinal cord.
The Central Nervous System (CNS)
The Central Nervous System (CNS) is composed of
Brain
Spinal cord
The ______ serves as the control center of the body.
Brain (CNS)
Brain
Is the control center of the body. (CNS)
The ___________ serves as the passageway for nerve impulses.
spinal cord
spinal cord
the passageway for nerve impulses.
It is composed of neurons outside the central nervous system.
The Peripheral Nervous System (PNS)
The Peripheral Nervous System (PNS) is composed of
neurons outside the central nervous system.
They communicate through electrochemical signals or nerve impulses.
Neurons (PNS)
These are the nervous system’s most basic cell units, also called ______ cells.
neurons, nerve
They transmit signals in the form of electrical impulses or chemical signals.
Neurons (PNS)
Parts of A Neuron
● Dendrites
● Axon
● Soma
● Terminal button
● Synapse
Parts of A Neuron: _________ are the short, tree-like extensions of nerve cells, along which electrical impulses are received from other cells.
Dendrites
Dendrites
Dendrites are the short, tree-like extensions of nerve cells, along which electrical impulses are received from other cells. (Part of a Neuron)
Parts of A Neuron: ________ are the long transmitting parts that conduct electrical impulses away from the nerve cell’s body.
Axons
Axons
Axons are the long transmitting parts that conduct electrical impulses away from the nerve cell’s body. (Part of a Neuron)
Parts of A Neuron: The _____ or the cell body of the neuron contains the cell’s nucleus and is responsible for regulating the actions of a neuron.
soma
soma
The soma or the cell body of the neuron contains the cell’s nucleus and is responsible for regulating the actions of a neuron. (Part of a Neuron)
Classification of Neurons
● Functional Classification
● Structural Classification
Types of neurons based on Functional Classification
● Sensory neurons
● Motor neurons
● Interneurons
These carry impulses from the body to the CNS and relay signals back to the spinal cord or the brain. These are also known as __________.
Sensory Neurons, afferent neurons (Functional Classification of Neurons)
Sensory Neurons
These carry impulses from the body to the CNS and relay signals back to the spinal cord or the brain. These are also known as afferent neurons. (Functional Classification of Neurons)
These carry impulses and signals back to the body from the central nervous system. They also known as _______.
Motor Neurons, efferent neurons (Functional Classification of Neurons)
These serve as connection points in between sensory and motor neurons. They are also known as ________.
Interneurons, association neurons (Functional Classification of Neurons)
Motor Neurons
These carry impulses and signals back to the body from the central nervous system. They also known as efferent neurons. (Functional Classification of Neurons)
Interneurons
These serve as connection points in between sensory and motor neurons. Interneurons are also known as association neurons. (Functional Classification of Neurons)
Typers of Neurons based on Structure Classification
● Multipolar Neuron
● Bipolar Neuron
● Unipolar Neuron
This contains one axon but multiple dendrites. It is capable of integrating large amounts of information because of multiple dendrites
Multipolar Neuron (Structural Classification of Neurons)
Multipolar Neuron
This contains one axon but multiple dendrites. It is capable of integrating large amounts of information because of multiple dendrites. (Structural Classification of Neurons)
This has two distinct nerve processes, usually in the form of one axon and one dendrite. This is commonly seen associated with sensory organs.
Bipolar Neuron (Structural Classification of Neurons)
Bipolar Neuron
This has two distinct nerve processes, usually in the form of one axon and one dendrite. This is commonly seen associated with sensory organs. (Structural Classification of Neurons)
Unipolar Neuron
This has one distinct nerve cell body. This is commonly seen associated with ganglia. (Structural Classification of Neurons)
This has one distinct nerve cell body. This is commonly seen associated with ganglia.
Unipolar Neuron (Structural Classification of Neurons)
Neuroglial Cells in the Central Nervous System
● Astrocyte
● Ependymal cell
● Microglial cell
● Oligodendrocyte
These are named for their stellar shape and also known as ________. These are for structural support for the brain, tissue repair, modulation, and metabolic regulators.
Astrocyte, astroglia (Neuroglial Cells in the Central Nervous System)
Astrocyte
These are named for their stellar shape and also known as astroglia. These are for structural support for the brain, tissue repair, modulation, and metabolic regulators. (Neuroglial Cells in the Central Nervous System)
These act as the defenders of the CNS against infections. These are macrophages and serve the function of destroying pathogens.
Microglial Cells (Neuroglial Cells in the Central Nervous System)
Microglial Cells
These act as the defenders of the CNS against infections. These are macrophages and serve the function of destroying pathogens. (Neuroglial Cells in the Central Nervous System)
These produce cerebrospinal fluid, which is a fluid that acts as a cushioning agent for the CNS.
Ependymal Cells (Neuroglial Cells in the Central Nervous System)
Ependymal Cells
These produce cerebrospinal fluid, which is a fluid that acts as a cushioning agent for the CNS. (Neuroglial Cells in the Central Nervous System)
These are also known as _____________. They produce the myelin that makes up the myelin sheaths of the cells of the CNS.
Oligodendrocytes, oligodendroglia (Neuroglial Cells in the Central Nervous System)
Oligodendrocytes
These are also known as oligodendroglia. They produce the myelin that makes up the myelin sheaths of the cells of the CNS. (Neuroglial Cells in the Central Nervous System)
_________ are the most abundant neuroglial cells in the CNS.
Astrocytes
___________ are phagocytic cells in the CNS.
Microglial cells
____________ line cerebrospinal fluid-filled cavities.
Ependymal cells
Neuroglial Cells in the Peripheral Nervous System
● Satellite cells
● Schwann cells
● Myelin sheath
● Myelinated Sheath
_________ are found as coatings of the nerve cells of the PNS.
Satellite cells (Neuroglial Cells in the Peripheral Nervous System)
Satellite cells
Satellite cells are found as coatings of the nerve cells of the PNS. (Neuroglial Cells in the Peripheral Nervous System)
___________ are the PNS equivalent of oligodendrocytes that produce myelin for the nerve cells.
Schwann cells (Neuroglial Cells in the Peripheral Nervous System)
Schwann cells
Schwann cells are the PNS equivalent of oligodendrocytes that produce myelin for the nerve cells. (Neuroglial Cells in the Peripheral Nervous System)
Concentric wrapping of Schwann cells around the axon forms the __________.
myelin sheath
____________ is used for insulating the electrical signals for a more efficient transmission. Concentrated schwann cells around the axon form this.
Myelin sheath
Myelin sheath
Myelin sheath is used for insulating the electrical signals for a more efficient transmission. Concentrated schwann cells around the axon form this.
In a myelinated axon, periodic breaks called _____________ is evident. Its purpose is to speed up the impulse propagation along the fiber.
Myelinated sheath, node of Ranvier (Neuroglial Cells in the Peripheral Nervous System)
Functional Systems of the Nervous System
● Sensory systems
● Motor systems
● Associational systems
_____________ are the “input” systems of the body that includes all the senses.
Sensory systems (Functional Systems of the Nervous System)
Sensory System
Sensory System are the “input” systems of the body that includes all the senses. (Functional Systems of the Nervous System)
______________ are the “output” systems of the body which respond to the information gathered by the sensory systems.
Motor systems (Functional Systems of the Nervous System)
Motor systems
Motor systems are the “output” systems of the body which respond to the information gathered by the sensory systems. (Functional Systems of the Nervous System
_______________ serve as “mediator between the sensory and the motor systems.”
Associational systems (Functional Systems of the Nervous System)
Associational systems
Associational systems serve as “mediator between the sensory and the motor systems.” (Functional Systems of the Nervous System)
The systems work together to ensure that all information are perceived and a proper response to every processed information is elicited.
Functional Systems of the Nervous System
Functions of the Nervous System
● Transmitting Signals
● Sensory Purposes
● Movement
● Processing Information
● Mental Activity
Signals are transmitted by the main cells of the nervous system, the neurons.
Transmitting Signals
Signals in the nervous system can either be __________ or ___________.
electrical, chemical signals
allows electrical signal to be passed via movement of ions.
Action potential (Transmitting Signals)
Action potential
Action potential allows electrical signal to be passed via movement of ions. (Transmitting Signals)
allow chemical signals to be passed from neuron to neuron.
Neurotransmitters (Transmitting Signals)
Neurotransmitters
Neurotransmitters allow chemical signals to be passed from neuron to neuron. (Transmitting Signals)
Integrating Functions of Different Organ Systems
A large number of the functions performed by the different organs and organ systems are regulated and controlled by the nervous system. Many of the interactions between organ systems are also controlled and regulated by the nervous system.
