PNS: Somatic Sensory, Visceral Sensory, Somatic (Voluntary) Motor, Visceral (Involutary) Motor.
Where are the general somatic senses found?
Outer part of the body
What is the name for the branch that send signals towards the cell body?
Dendrites.
What sense detects stretch in tendons and muscles; give body sense of position and movement of body in space?
Proprioceptive sense
What are all the neuroglia cells?
Astrocytes, microglia, ependymal cells, oligodendrocytes.
What are the special somatic senses?
Hearing, Equilibrium, Sight, Smell
What are the signals picked up by sensor receptors and carried by nerve fibers of the PNS into the CNS?
Motor signals are carried away from the CNS?
Afferent
Efferent
What are the special visceral senses?
Taste
What are Nissl Bodies and Neurofibrils
What cell body is not in CNS?
Nissl Bodies: Clusters of rough ER and free ribosomes that stain darkly and renew membranes of the cell
Neurofibrils: bundles of intermediate filaments; form a network between chromatophilic bodies.
Ganglia is not in the CNS
What are the special characteristics of neruons? (3)
Longevity
DO NOT DIVIDE: Fetal neurons lose their ability to undergo mitosis.
High Metabolic rate
What neuron transmits afferent impulses to the CNS.
T/F An Effector is muscle or gland cell; responds to efferent impulses; contracting or secreting
Sensory Neuron
True
What are the differences between somatic reflexes and visceral reflexes?
somatic reflexes: Resulting in the contraction of skeletal muscles.
Visceral reflexes: Activating smooth muscle, cardiac, or glands.
What are cordlike organs in the PNS; consisting of numerous axons (nerve fibers) arranged in parallel bundles wrapped in C.T.?
Neurons
What is the difference between the Perineurium and the Epineurium.
Perineurium: C.T. wrapping surrounding a nerve fascicle
Epineurium: whole nerve is surrounded by tough fibrous sheath
T/F Astrocytes form the myelin sheaths in the brain and spinal cord
T/F Thick axons are myelinated and thin axons are unmyelinated
False, Its Oligodendrocytes.
True
What is formed by Schwann cells, which wrap in concentric layers around the axon… creating a tightly packed coil of membranes?
Myelin Sheath
T/F Myelin Sheaths form an insulating layer and increases the speed of impulse conduction.
What are the two kinds of supporting cells in the PNS?
True
Satellite cells and Schwann cells
What are the three less common types of synapses?
What is the site at which neurons communicate?
Axoaxonic, dendrodendritic, and dendrosomatic
Synapses
T/F Dendrites are the chemical messenger molecules that excite or inhibit neurons.
What provide structural strength along length of axon; aid in the transport of substances to and from the cell body?
False its Neurotransmitters.
Neurofilaments, actin microfilaments, and microtubules
T/F Dendrites transmit impulses away from the cell body; no protein synthesis in axon?
What are the basic structural units of the nervous system.
False its axons
Neurons