CIS Physiology content quiz 1 tri 2

What are the three divisions of the nervous system?

The Central Nervous System (CNS), the Peripheral Nervous System (PNS), and the Enteric Nervous System (ENS).

Where does the functional organization of the nervous system begin?

The collection of sensory information by receptors.

Which division of the PNS brings information to the CNS?

The sensory division of the peripheral nervous system.

Which division of the PNS controls the somatic and autonomic nervous systems?

The motor division of the peripheral nervous system.

What are neurons specialized for?

Intracellular communication.

How do neurons collect information about their environment?

Via receptors.

How might an increase in the number of telodendria improve communication?

This might improve cell-to-cell communication.

What is the general function of glial cells?

Glial cells support neurons and their functions.

What is the role of Ependymal Cells?

Responsible for the production of Cerebrospinal Fluid (CSF).

What is the role of Microglia?

Perform various protective and specialized roles.

What is the role of Astrocytes?

They promote the formation of the Blood-Brain Barrier (BBB).

What is the role of Oligodendrocytes?

They myelinate neurons within the CNS.

What is the role of Schwann Cells?

They myelinate neurons in the PNS.

What is the role of Satellite Cells?

They surround neuron cell bodies in the PNS.

What process occurs after injury during axon regeneration in the PNS?

Wallerian degeneration.

What are the two main purposes of Cerebrospinal Fluid (CSF)?

CSF provides physical protection and chemical protection for the brain and spinal cord.

How does CSF physically protect the brain?

It cushions the brain against physical trauma and reduces the brain's weight nearly 97%.

Where is CSF continuously secreted?

By the choroid plexus.

What specialized neuroglia cells produce CSF?

Specialized ependymal cells.

How does the choroid plexus draw water out of the blood?

By selectively pumping sodium and other solutes from the blood plasma.

How does CSF flow through the CNS?

CSF flows from the ventricles into the subarachnoid space.

How is CSF absorbed back into the blood?

By specialized structures called villi (or arachnoid granulations).

How does the composition of CSF differ from blood plasma?

CSF contains less protein and lower concentrations of K+ than plasma, but higher concentrations of H+.

What does the presence of proteins or blood cells in CSF indicate?

It typically indicates infection.

What functional barrier protects the brain?

The Blood-Brain Barrier (BBB).

What is the main role of the BBB?

To protect the brain and separate the blood from the interstitial fluid surrounding the neurons.

What are neurons?

Cells specialized for transmitting nerve impulses.

What are glial cells?

Supportive cells in the nervous system that do not conduct impulses.

What is myelination?

The process of forming a myelin sheath around a nerve to increase the speed of impulse transmission.

What is the function of the Blood-Brain Barrier (BBB)?

It isolates the brain's central control center from potentially harmful substances in the blood.

What structural features make brain capillaries unique?

Tight junctions between the endothelial cells of the brain capillaries.

How do astrocytes promote the formation of the BBB?

Astrocyte foot processes surround the brain capillaries and secrete paracrine signals that promote tight junction formation.

What types of substances pass freely across the BBB?

Lipid-soluble substances, such as oxygen, carbon dioxide, fats, fatty acids, alcohol, nicotine, and anesthetics.

What substances rely on specific transport mechanisms to cross the BBB?

Nutrients such as glucose and amino acids.

What must the BBB be permeable to for neurons?

Glucose, which is transported across the BBB by membrane transporters.

What common solutes are generally impermeable to the BBB?

Water-soluble molecules, blood-borne metabolic wastes, proteins, certain toxins, nonessential amino acids, and K+ ions.

Where in the brain is the BBB incomplete, allowing it to sample blood composition?

The Hypothalamus.

Where in the brain is the BBB incomplete, allowing for toxin monitoring?

The Vomiting Center in the medulla oblongata.

What does CNS stand for?

Central Nervous System.

What does PNS stand for?

Peripheral Nervous System.

What does ENS stand for?

Enteric Nervous System.

What are receptors?

Structures used by neurons to collect information about their environment.

What are telodendria?

Structures whose number increases when neurons are frequently used, improving cell-to-cell communication.

What are anaxonic neurons?

One of the four major anatomical classes of neurons.

What are bipolar neurons?

One of the four major anatomical classes of neurons.

What are unipolar neurons?

One of the four major anatomical classes of neurons.

What are multipolar neurons?

One of the four major anatomical classes of neurons.

What are glial cells (neuroglia)?

Cells that support neurons and their functions.

What are ependymal cells?

Neuroglia of the CNS responsible for the production of Cerebrospinal Fluid (CSF).

What are microglia?

Neuroglia of the CNS.

What are astrocytes?

Neuroglia of the CNS that promote the formation of the Blood-Brain Barrier (BBB).

What are oligodendrocytes?

Neuroglia responsible for myelination within the CNS.

What are Schwann cells?

Neuroglia of the PNS responsible for myelination in the PNS.

What are satellite cells?

Neuroglia of the PNS that surround neuron cell bodies.

What is Wallerian degeneration?

The process predicted to occur after injury during axon regeneration within the PNS.

What is cerebrospinal fluid (CSF)?

A salty solution that provides physical and chemical protection for the brain and spinal cord.

What is the choroid plexus?

A specialized region in the walls of the ventricles that continuously secretes CSF.

What are ventricles?

Locations in the brain where specialized ependymal cells line the walls and form the choroid plexus.

What is the osmotic gradient in CSF?

The mechanism created when specialized ependymal cells selectively pump sodium and other solutes from plasma into the ventricles.

What is the subarachnoid space?

The area between the pia mater and the arachnoid membrane where CSF flows.

What are villi (arachnoid granulations)?

Specialized structures on the arachnoid membrane that absorb CSF back into the blood.

What is L-dopa?

A dopamine precursor that is transported across the BBB using an amino acid transporter.

What is the hypothalamus?

A brain region that lacks a complete BBB, allowing it to monitor the chemical composition of the blood.

What is the vomiting center?

A region in the medulla oblongata that lacks the BBB, allowing neurons to monitor the blood for toxins.

What is glucose?

The primary energy source for neurons, which must be transported across the BBB.

What are lipid-soluble substances?

Substances that can pass freely across the BBB via simple diffusion.