Lecture 18- Nervous System Organisation Flashcards
What type of nervous system organization do Cnidarians have?
Nerve net
What type of nervous system organization do Echinoderms have?
Nerve ring
What type of nervous system organization do Bilateral have?
Brain, most clearly defined central nervous system
What type of nervous system organization do Annelids & Arthropods have?
Brain
Ganglia- Sets of neurons, segmentally arranged clusters
What type of nervous system organization do vertebrates have?
CNS- Composed of spinal cord and brain
PNS- Composed of ganglia and nerves
Chitin vs. Squid
Chitin- slow moving -> simple
Squid- fast moving -> complex
Adult Glial Cells (list)
Astrocytes
Ependmyal cells
Microglial cells
What is the function of an astrocyte?
Support the blood brain barrier (neurons)
What is the function of a microglial cell?
Scavengers, cleanup, cell fragments
“Picking up microplastics”
What is the function of an ependymal cell?
Cerebral spinal fluid
It rhymes
What is myelination?
The formation of a sheath around nerve fibers, or axons.
Myelination in CNS versus PNS (what does it)
CNS- Oligodendrocytes
PNS- Shwann cells
What do the Oligodendrocytes do?
They do myelination in the CNS. They are formal, they give the axon a “handshake”. (They have appendages that reach out and grab onto axons to myelinate them)
What do the Schwann cells do?
They are in the PNS. They are less formal, give the axon a “hug”. (The whole Shwann cell is wrapped around axon)
What are the two components of the CNS?
Brain and spinal cord