Nervous system (CB) Flashcards
Which systems play the most important role in maintaining homeostasis in the body?
The nervous and endocrine system
3 basic functions of the nervous system
- Detecting stimuli (sensory function)
- Analyzing integrating, and storing sensory information (Integrative function)
- Responding to integrative decisions (motor function)
Organisation of the nervous system
CNS:
* Brain
* Spinal cord
PNS:
* Cranial nerves
* Spinal nerves
* Ganglia
* Enteric plexuses in small intestine
* Sensory receptors in skin
Neurology
The branch if medical science that deals with normal functioning and disorders of the nervous system
What does the central nervous system (CNS) consist of?
Brain and spinal cord
What does the peripheral nervous system (PNS) consist of?
All nervous tissue outside the CNS
Components of the PNS
- Nerves
- Ganglia
- Enteric plexuses
- Sensory receptors
Systems the PNs are divided into?
- Somatic nervous system (SNS)
- Autonomic nervous system (ANS)
- Enteric nervous system (ENS)
Somatic nervous system (SNS)
Sensory neurons that conduct impulses from somatic and special senses receptors to the CNs and motor neurons from the CNS to skeletal muscles
Autonmic nervous system (ANS)
Sensory neurons from visceral organs and motor neurons convey impulses from the CNS to smooth muscle tissue, cardiac muscle tissue and glands
* Motor part of ANS consists of two branches the sympathetic division and the parasympathetic division
Sympathetic division
Helps support exercise and emergency actions or “fight-or-flight” responses
parasympathetic divison
parasympathetic division takes care of “rest-and-digest”
Enteric nervous system (ENS)
Consists of neurons in enteric plexuses in the gastrointestinal (Gi) tract that function somewhat independently of the ANS and CNS. The ENS monitors sensory changes in and controls the operation of the GI tract.
Two types of cells nervous tissue consists of?
- Neurons
- Neuroglia
Two types of cells nervous tissue consists of - Neurons
Neurons are cells specialized for nerve impulse conduction and provide most of the unique functions of the nervous system, such as sensing, thinking, remembering, and controlling muscle activity
Two types of cells nervous tissue consists of - Neuroglia (glue)
Support, nourish, and protect the neurons and maintain homeostasis in the interstitial fluid that bathes neurons.
axon
Conducts nerve impulses toward another neuron, muscle fiber, or a gland cell
3 c structural classifications of neurons
- Multipolar
- Bipolar
- Unipolar
functional classifications of neurons
- Sensory (afferent) neurons
- Motor (efferent) neurons
- Interneurons
What does the neuroglia in the CNS include?
- Astrocytes
- Oligodendrocytes
- Microglia
- Ependymal cells
What does the neuroglia in the PNS include?
- Schwann cells
- Satellite cells
What does the neuroglia in the CNS include - Oligodendrocytes
Produce and maintain myelin sheath around several adjacent axons of CNS neurons
What does the neuroglia in the CNS include - Ependymal cells
Line ventricles of the brain (cavities filled with cerebrospinal fluid) and the central canal of the spinal cord; form a cerebrospinal fluid and assist in the circulation
What does the neuroglia in the CNS include - Satellite cells
Support neurons in PNS ganglia and regulate the exchange of materials between neurons and interstitial fluid
Histology of nervous tissue - White matter
Composed primarily of myelinated axons
Histology of nervous tissue - Gray matter
Contains neuronal cell bodies, dendrites, axon terminals of neurons, unmyelinated axons, and neuroglia
* In the spinal cord, gray matter forms an H-shaped inner core that is surrounded by white matter. In the brain a thin superficial shell of gray matter overs the cerebrum and cerebellum
Clusters of neuronal cell bodies (ganglion)
Refers to a cluster of neuronal cell bodies located in the PNS. As mentioned earlier, ganglia are closely associated with cranial and spinal nerves . By contrast, a nucleus is a cluster of neuronal cell bodies located in the CNS
Bundles of Axons
A nerve is a bundle of axons that is located in the PNS. Cranial nerves connect the brain to the periphery; spinal nerves connect the spinal cord to the periphery. A tract is a bundle of axons that is located in the spinal cord and brain
