Nervous System Flashcards
How does a protein isolated from jellyfish help with sorting out functional connections?
They took the green fluorescent protein, and mutated it to create proteins that are different colours of fluorescence. Each cell is a different colour code, so you can trace the path of particular cells through nervous systems.
What do sponges lack?
nerves
How do sponges get by without having nerves?
having connections between cells that do not involve the excitation of cells and communicate by neurotransmitters
What network do Cnidarians have that help with their digestive system?
have a diffuse net or nerves that wraps around the whole body, and this network lets them open and close their digestive and move their arms a bit to get some plankton
What arrangement of neurons do flatworms have, and how is it beneficial?
segmental arrangement of neurons, and beneficial because it allows it to control its body movements
What is cephalization?
the concentration of sense organs, nervous control, etc., at the anterior (top of the animal) end of the body, forming a head and brain, both during evolution and in the course of an embryo’s development.
What happened to the planarian that was unable to use environmental cues from earth because it was on space for its pathways of regeneration?
when deprived of that sensory feedback, they did not know whether or not to make a replacement head or tail
How do neurons collect info?
dendrites
What do the axons do?
transmit signals to the next cell
What is the myelin?
-macromolecule sheath
-wraps around the axon
-provides insulation that accelerates propogation (spreading) of the action potential down the axon
-in the CNS it is made by oligodendrocyte cells
-in the PNS made by the Schwann cells
What are glia?
non neuronal cells within the CNS.
What role do the glia play?
protecting the CNS from infections
What are the capillaries composed of?
endothelial cells.
Why do endothelial cells have tight connections?
to prevent material from leaking from the circulation into the brain’s interstitial fluid
why are the connections between the cells in the hypothalmus not as tight?
permits the region to sample circulation
How it capillary integrity controlled?
by astrocytes
What do astrocytes do?
sense the environment, and when the immune system is called into action, astrocytes inform the capillaries on whether or not to alter permeability.
what is the grey matter of the brain made up of?
largely unmyelinated neurons, cell bodies, dendrites, glia
What is the white made up of, and what makes it “white”?
-made from a collection of myelinated neurons
-whiteness coming from the myelin sheaths
What does the spinal cord work as?
-tract for neurons from the brain
-second brain to control pattern generation and respond to sensory events associated with reflex
What does the CNS include?
brain and spinal cord
What is the PNS?
-peripheral nervous system
-the nerves that branch out from the brain and spinal cord
What are reflexes a good example of?
-benefits of a complicated nervous arrangement of the CNS
What would happen if a doctor were to wack someone in the kneecap, what would be the chain reaction?
-mechanical stimulation creates an event that the muscle recognizes and needs to contract
-sensory neuron picks up a signal from the connective tissue near the muscle
-send one signal to the spinal cord, then back to the motor neuron to tell the quad to contract
-also sends a signal to the inter-neuron which translates that into a signal that tells the hamstring not to contract
-ensures our leg extends
