Unit 10 Flashcards
What does our nervous system allow us to sense?
Homeostasis
How many nervous systems are there?
One
CNS process and evaluates which responds to what?
Motor nuerons –> in PNS to Effectors (muscles or glands)
Nervous system has tow functional divisions of the nervous system:
Sensory and motor division.
What does afferent mean?
Inflowing or towards the century of activity
Is sensory division afferent or efferent ?
Afferent )receiving sensory information from receptors and transmitting this information.
True or False: The sensory division contains both PNS and CNS components?
True
Explain the Somatic Sensory and Visceral Sensor:
Somatic: components are the general somatic sense; touch, pain, pressure, temperatures and proprioception VOLUNTARY
What are the two distinct cell types from nervous tissue?
Neurons: excitable cells that initiate and transmit nerve impulse
Glia: nonexcitabel cells that support and protect the neurons.
Give some facts of Neurons:
- High metabolic rate, and supply of O2 and Nutrients
- Extreme longevity and often survive form initial development in the womb to old age
- Neurogenesis
T/F: The cell body serves as the neurons control center and is reusable for transmitting impulses?
False: responsible for receiving, integrating, and sending nerve impulses (it also contains nucleus and many mitochondria)
What do Cytoplasmic projection are called what?
dendrites (tree) and they conductive nerve impulses toward the cell body
Are all axons cytoplasmic projections?
Yes
What way do Axons transmit impulses?
Away from the cell body
Where are the Sensory (afferent) neurons located?
outside the CNS to muscles or glands
Motor (efferent) neurons cell bodies are located mostly where?
in the spinal chord, whereas the axons primarily travel in the cranial or spinal nerves to muscles and glands.
What estimation is given for how many interneurons are in our body?
99%
What is referred to as neuroglia and is found in the CNS and PNS.
Glial Cells
How do Glial cells differ?
They are smalls and capable of mitosis erecting theme and by providing a suppuration framework, unlike neurons.
Do glial cells transmit impulses ?
No
Name the 4 different types of Glial Cells
Astrocytes, Ependymal, Microglia, and Oligodendrocytes.
What is the most abundant glial cells?
Astrocytes
What Glial Cells wrap around the capillaries in the brain?
Astrocytes
What is BBB made of?
Capillaries and astrocytes (which are less leaky).
What does the BBB do?
Protects the delicate brain from toxins (certain waist products and some drugs)
What Glial class line the internal cavities (ventricles) fo the brain and central canal of the pistol cord?
Ependymal
What do the Ependymal cells and nearby the blood capillaries create?
Choroid plexus cells
What cells create the CSF?
The choroid plexus
Where does CSF reside?
the CNS and fills its internal cavities.
What helps circulate the CSF?
Ependymal cells that have cilia on their surface the help circulate the CSF
What type of Glial cells are wandering phagocytic cells and remove cellular debris thought the CNS
Microglial (small) cells
Which type of Glial cell are large cells with slender cytoplasmic processes that ensheath portions of axons by repeatedly wrapping around an axon like electrical tape wrapped around a wire.
Oligodendrocytes
What two types of glial cells are in the PNS, and explain their function.
Satellite cells: flattened cells arranged around neuronal cell bodies in ganglia and help regulate the movement of nutrients and waste products between neurons and environment.
-Shawn Cells: responsible for myelinating PNS axons.
What do you call a cable-like bundle of parallel axons.
Nerve
Name the nerves and the functions fo the PNS:
-Sensory nerves: convey sensory info to the central nervous system and all axons are conducting impulses in the same direction
-Motor Nerves: convey motor impulses from the centra nervous system to the muscles and glands and all the axons are conducting impulses in the same direction.
-Mixed nerves:
Carry both types of information and some axons are transmitting impulses in one direction, while other axons are transmitting impulses in the opposite direction.
When does nervous tissue develop in the embryo?
During the third week of development
What appears in the developing tissue and causes fusion along the midline to form a neural tube?
Neural Groove.
Where is the neural tube located?
Has an opening near the future head and an opening near the future buttocks.
What is neural tube defect?
When openings do not close.
What two projections happen during the developing neural tube of the CNS?
- The cranial part of the neural tube expansion to form the brain
- The caudal part of the neural tube expanse to form the spinal cord.
