Exam 4: Principles of Neural and Hormonal Communication

Indicate which characteristic applies to classical neurotransmitters and neuropeptides. a.neurotransmitters b.neuropeptides c.both neurotransmitters and neuropeptides d.neither neurotransmitters nor neuropeptides -Synthesized in cytosol of synaptic knob

Classical neurotransmitters and neuropeptides are sometimes co-secreted from the same axon terminal.

Myelinated axons conduct impulses much faster because

Indicate whether the membrane is more permeable to K⁺ or to Na⁺ or is equally permeable to these ions under the stated conditions: a.more permeable to K+ than to Na+ b.more permeable to Na+ than to K+ c.equally permeable to Na+ and K+ -During the falling phase of an action potential

Schwann cells promote axonal growth, while oligodendrocytes inhibit it.

Match neural disease/influence with correct characteristic. a.multiple sclerosis b.tetanus c.strychnine d.roseola e.Parkinson's disease -May predispose a person to multiple sclerosis

At the peak of an action potential,

Indicate the direction that the force in question tends to move the involved ion under the stated conditions by writing the appropriate letter in the blank, using the following answer code: a.tends to move the involved ion out of the cell b.tends to move the involved ion into the cell -Concentration gradient for Na⁺ at the end of an action potential

Match neural disease/influence with correct characteristic. a.multiple sclerosis b.tetanus c.strychnine d.roseola e.Parkinson's disease -Competes with glycine for receptors

Nerve fiber is another name for a dendrite on a neuron.

The ____________________ or ____________________ of a neuron is a single, elongated tubular process that conducts action potentials away from the cell body and eventually terminates at other cells.

In a graded potential, the direction of current flow is designated by the movement of positive charges.

Choose the match for each substance listed. a.covering on the axon b.second messenger c.branching process from a cell body d.impulse-conducting region e.junction between neurons f.neurotransmitter -Synapse

In convergence,

Which statement is true about the absolute refractory period?

The diffusion of potassium ions reestablishes the resting membrane potential in a neuron immediately after it develops an action potential.

____________________ are chemical messengers that bind to neuronal receptors at nonsynaptic sites and alter the effectiveness of ongoing synaptic activity.

Which statement about a graded potential is false?

Indicate the direction that the force in question tends to move the involved ion under the stated conditions by writing the appropriate letter in the blank, using the following answer code: a.tends to move the involved ion out of the cell b.tends to move the involved ion into the cell -Concentration gradient for K⁺ at the end of an action potential

Which term best describes an excitable cell when a resting membrane potential is present?