The PNS has two kinds of neuroglia:
schwann cells
and satellite cells
Which division of the peripheral nervous system only Innervates the gastrointestinal tracts wall?
Which division of the peripheral nervous system only innervates the gastrointestinal tract’s wall?
somatic and sympathetic divisions
.
What happens when a graded potential Summates to threshold at the axon hillock?
When a graded potential summates to threshold at the axon hillock,
voltage-gated Na+ channels open rapidly.
What is the function of Neuroglial cells quizlet?
What is the function of neuroglial cells? Neuroglial cells are
support cells, helping to support neurons to enable them to thrive in their needed environment
.
Which structure is a common site of protein synthesis in neurons?
The cell body contains
the nucleus
and is the site of synthesis of virtually all neuronal proteins and membranes. Some proteins are synthesized in dendrites, but no proteins are made in axons and axon terminals, which do not contain ribosomes.
Which nervous system primarily controls and increases salivation group of answer choices?
In the histologic sections of canine salivary gland shown above, the cells stained pink are serous cells, while the white, foamy cells are mucus-secreting cells. Secretion of saliva is under control of
the autonomic nervous system
, which controls both the volume and type of saliva secreted.
Why is gut called second brain?
The enteric nervous system (ENS) is known as the “second brain” or the brain in the gut
because it can operate independently of the brain and spinal cord, the central nervous system (CNS)
. It has also been called the “first brain” based on evidence suggesting that the ENS evolved before the CNS.
What happens just after an axon is depolarized to threshold?
What happens just after an axon is depolarized to threshold?
Some potassium channels open. All potassium channels open. All sodium channels open
.
What is the difference between a graded potential and an action potential?
Graded potentials are brought about by external stimuli (in sensory neurons) or by neurotransmitters released in synapses, where they cause graded potentials in the post-synaptic cell. Action potentials are triggered by membrane depolarization to
threshold
.
What causes a graded potential to degrade?
A graded potential is produced
when a ligand opens a ligand-gated channel in the dendrites, allowing ions to enter (or exit) the cell
. The graded potential will degrade with distance, so it would decrement before reaching the end of the axon if an action potential were not generated. …
What is the function of Neuroglial cells?
The neuroglia are a diverse class of cells that provide developmental, physiological, and metabolic support for neurons. They are responsible for
maintaining homeostatic control and immune surveillance in the nervous system
.
What are three functions of the neuroglia?
- The formation of the blood-brain barrier.
- Provision of nutrients for neurons.
- Structural support for nerve cells.
- Release and absorption of ions and neurotransmitters for improved modulation of cell-to-cell communication between neurons.
- Repair of the nervous system.
Which Neuroglial cell helps form the blood-brain barrier?
Astrocytes
also form the blood-brain barrier—a structure that blocks entrance of toxic substances into the brain.
What is the site of protein synthesis in the cell?
Ribosomes
are the sites in a cell in which protein synthesis takes place.
What is the small gap between neurons called?
The axon of one neuron and the dendrite of the next are separated by a tiny gap called
a synapse
. Once an electric impulse reaches the end of an axon, it stimulates the release of chemicals called neurotransmitters into the gap in order to communicate with the next neuron in the pathway.
Why do motor neurons have long axons?
The axon brings the message to the target of the nerve cell. Most of the cell bodies of the human nerves are located in the brain and in the spinal cord. Axons have to be long in
order to reach every part of your body from the central regulating places in the brain and the spine
.
