week 3

What is the composition of grey matter in the CNS?
A. Mainly non-myelinated neurones, glial cells, and blood vessels 
B. Lightly myelinated nerve fibres that connect entirely within the CNS
C. Slightly pigmented non-myelinated nerve fibres
D. Non-myelinated sensory nerve fibres going from the spinal cord to the thalamus
E. Connective tissue and blood vessels supplying the white matter

The autonomic nervous system is subdivided into theSelect one:
A. central and peripheral divisions.
B. Central and enteric divisions.
C. visceral and somatic divisions.
D. somatic and enteric divisions.
E. sympathetic, parasympathetic, and enteric divisions. 

Presynaptic inhibitionSelect one:
A. Occurs only in the autonomic nervous system
B. Modulates the amount of neurotransmitter released. 
C. Always involves neurons acting in each other
D. Reduces the rate of neurotransmitter synthesis
E. Occurs only in the central nervous system

Presynaptic modulation of neurotransmitter release involves modifying ________ at the axon terminal.Select one:
A. potassium channels
B. the vesicles selected for release
C. calcium influx 
D. sodium channels
E. the amount of neurotransmitter in the vesicle

Myelin is formed bySelect one:
A. oligodendrocytes.
B. ependymal cells.
C. Schwann cells.
D. C and D
E. axons.

The two divisions of the efferent side of the peripheral nervous system areSelect one:
A. voluntary nervous system and somatic motor neurons.
B. somatic motor neurons and voluntary neurons.
C. somatic motor neurons and autonomic neurons. 
D. the sympathetic and parasympathetic divisions.
E. central efferent and peripheral efferent systems.

The afferent and efferent axons together form theSelect one:
A. visceral nervous system.
B. somatic motor division of the nervous system.
C. central nervous system.
D. autonomic division system.
E. peripheral nervous system. 

Voltage-gated calcium channels in the axon terminal open in response to ________.Select one:
A. neurotransmitter binding to receptors
B. initiation of an action potential in the cell body
C. arrival of an action potential at the axon terminal 
D. paracrines released from the post-synaptic cell
E. summation of graded potentials at the cell body

When an action potential reaches a nerve ending it:Select one:
A. triggers uptake of neurotransmitters in vesicles
B. triggers neurotransmitter synthesis
C. returns back to the cell body
D. triggers the release of chemical transmitters 
E. inhibits release of transmitters

The brain and spinal cord together compose theSelect one:
A. autonomic division system.
B. peripheral nervous system.
C. somatic motor division of the nervous system.
D. visceral nervous system.
E. central nervous system.