Chapter 13: The Nervous System I: Nervous Tissue
The soma of a mature neuron lacks a.) a nucleus b.) endoplasmic reticulum c.) lipofuscin d.) centrioles e.) ribosomes
D.) Centrioles
Neurotransmitters are found in a.) the cell bodies of neurons b.) the dendrites c.) the axon hillock d.) the presynaptic terminal e.) the postsynaptic plasma membrane
D.) The Presynaptic Terminal
Nerves that directly control the motility of the stomach of rate of the heartbeat would belong to a.) the central nervous system (CNS) b.) the somatic sensory divison c.) the somatic motor division d.) the visceral motor division e.) the visceral sensory division
D.) The Visceral Motor Division
Astrocyte - CNS or PNS? What is it's function?
CNS - Form blood brain barrier (BBB), structure and organization of the CNS, nourishes neurons, and secrete growth stimulants.
Ependymal Cells - CNS or PNS? What is it's function?
CNS - Produce cerebrospinal fluid and form the choroid plexus.
Oligodendrocyte - CNS or PNS? What is it's function?
CNS - Produce myelin sheath.
Microglial Cells - CNS or PNS? What is it's function?
CNS - Remove cell debris from dead or dying cells.
In the PNS, the somas of the neurons are concentrated in enlarged, knot like structures called __________ connected to the nerves.
Ganglia
Bipolar
Two processes, one dendrite and one axon
What are the 3 functions of the nervous system?
- Collecting Information - Processing & Evaluating Information - Responding to Information
What are the 3 functional classifications of neurons?
-Sensory -Motor -Interneurons
The glial cells that guide migrating neurons in the developing fetal brain are a.) astrocytes b.) oligodendrocytes c.) satellite cells d.) ependymal cells e.) microglia
A.) Astrocytes
The glial cells that destroy microorganisms in the CNS are a.) microglia b.) satellite cells c.) ependymal cells d.) oligodendrocytes e.) astrocytes
A.) Microglia
Another name for the axon of a neuron is a.) nerve fiber b.) neurofibril c.) neurilemma d.) axoplasm e.) endoneurium
A.) Nerve Fiber
Neurons that convey information to the CNS are called sensory, or ___________, neurons.
Afferent
Prenatal degeneration of the forebrain results in a birth defect called ________.
Anencephaly
A/An _________ synapse is formed when a presynaptic neuron synapses with the cell body of a postsynaptic neuron.
Axosomatic
Which of the following appears earlier than all the rest in prenatal development of the nervous system? a.) the neural groove b.) a pair of primary vesicles c.) the neural plate d.) the neural crest e.) the neural tube
C.) The Neural Plate
Contrast electrical and chemical synapses.
Chemical synapse pass signals in the form of chemical molecules called neurotransmitters while electrical synapse transmits signals in the form of electrical signals without the use of molecules.
Neurons receive incoming signals by way of specialized processes called _____________.
Dendrites
Neurons arise from embryonic a.) Endoderm b.) Epidermis c.) Mesoderm d.) Mesenchyme e.) Ectoderm
E.) Ectoderm
The integrative functions of the nervous system are performed mainly by a.) Afferent Neurons b.) Efferent Neurons c.) Neuroglia d.) Sensory Neurons e.) Interneurons
E.) Interneurons
A friend takes a flash photograph of you, and you continue to see an image of the flash unite for several seconds afterward. This phenomenon is the result of a ___________ circuit. a.) diverging b.) converging c.) presynaptic d.) reverberating e.) parallel after-discharge
E.) Parallel after-discharge
What is the purpose of the myelin sheath?
It protects the axons.
Anaxonic
Many dendrites, NO AXON
Multipolar
Most common type of neuron; many dendrites and a single axon
The _________ and __________ are necessary for regeneration of damaged nerve fibers in the PNS.
Neurilemma and Endoneurium
In the CNS, cells called ________ perform one of the same functions that Schwann cells do in the PNS.
Oligodendrocytes
___________ are electrically excitable cells that transmit nerve signals.
Neurons
In a chemical synapse, when an electrical signal reaches the presynaptic terminal, synaptic vesicles fuse with the cell membrane to dump chemicals called ___________ into the ____________.
Neurotransmitters and Synaptic Cleft
Neurilemmocyte - CNS or PNS? What is it's function?
PNS - Produce myelin sheath but associated with PNS axons ONLY.
Satellite Cells - CNS or PNS? What is it's function?
PNS - Regulate exchange of nutrients and wastes.
All of the nervous system except the brain and spinal cord is called the __________.
Peripheral Nervous System (PNS)
At a given synapse, the __________ neuron has neurotransmitter receptors.
Postsynaptic
Motor effects that depend on repetitive output from a neural pool are most likely to use the __________ type of neural circuit.
Reverberating
Two functional divisions of the PNS are?
Sensory Nervous System (AFFERENT) (Sit on your aff) Motor Nervous System (EFFERENT) (Get the eff out of here)
Unipolar
Single, short process that branches like a T.