Science Section 1 Flashcards
Why are microglial cells critical to the nervous system?
They are the central nervous system’s only immune cells ( as a result of it being isolated by the BBB) to fight off infection
What is the function of Schwann cells and oligodendrocytes?
They both myelinate the axons of neurons as glial cells
What is the difference between oligodendrocytes and Schwann cells?
Oligodendrocytes myelinate axons of the CNS while Schwann cells myelinate axons of the PNS
How do astrocyte glial cells regulate the extracellular fluid in between cells in the nervous system?
As the most common glial cells, astrocytes remove the signaling molecules and keep a balance of ions.
What is the blood brain barrier?
Partly formed by astrocytes, the blood brain barrier (BBB) keeps certain substances from entering the brain and potentially damaging the neurons.
How does the restriction of the blood brain barrier affect the brain?
- Keeps the brain healthy
- Much more difficult to deliver drugs to help treat diseases
- Nutrients have less across to the nourish the brain
What is the function of the axon?
Used for transmitting output signals from one neuron to another or a muscle. No organelles in the axon.
What is the myelin and its function?
Myelin is a fatty substance made by glial cells that is meant to insulate the axon for faster and more efficient transmitting output signals
What is the function of the medulla (oblongata)?
Its nuclei relay touch sensation from the face, hearing, balance, swallowing food, vomiting, and other critical functions
-Has a rectangular shape
What is the brainstem?
The “stalk” at the bottom of the brain that connects the rest of the brain to the spinal cord. Most of the nuclei it has controls breathing, heart rate, reflexes, and coordination. Directly underneath the thalamus. Includes three subdivisions; medulla, pons, and the midbrain.
Describe the spinal cord
- Encased in vertebrae (back bone)
- White matter is on the outside of the cord, with grey matter on the inside
- Divided into sections
- Nerves run in between each vertebrae
True or False? The brain stem only consists of grey matter hence its nuclei.
False. Axons entering or exiting the brain must pass through the brainstem. That means there is white matter (myelinated axons) along with clusters of nuclei (grey matter)
What are the sections of the spinal cord?
Cervical, thoracic, lumbar, sacral (top to bottom)
What is the cervical spinal cord meant to control?
innervates with the amrs, neck, and shoulders
Thoracic spinal cord
deals with the chest and torso
Lumbar spinal cord
innervates with the hips and front of the legs
Sacral spinal cord
innervates with the buttocks and back legs
What is the ventricular system?
a series of interconnected cavities or hollow hole (ventricles) in the central nervous system that is filled cerebrospinal fluid (CSF)
What is the lateral ventricle?
A large CSF filled cavity located on both of the cerebral hemisphere near the left and right thalamus at the third ventricle which connects the two lateral ventricles (it’s located at the midbrain)
What connects the third and fourth ventricle?
The cerebral aqueduct is a narrow cavity in the midbrain of the brain stem that connects the third and fourth ventricle (located in the pons and medulla)
Where is the CSF located in the spinal cord?
In the central canal which is a narrow tube in the middle of the cord
What is the difference between glial cells and nerves?
Glial cells are non-neuronal cells and can be reproduced throughout the life of an organism thorugh mitosis
How does a neuron receive synaptic input from other neurons?
Through the dendrites.
This ability does depend on the shape/size of the dendrites.
What language does the word “dendrites” originate from?
Comes from the Greek word for “treelike”