Cells & Tissues (Nervous) Flashcards
Name and describe the 3 functions of nervous tissue (in general).
Sensory: detects stimuli and transfers to CNS.
Integrative: analyses and stores info.
Motor (Effector): Stimulates effectors through PNS.
What are the 3 functions of the nervous system?
Homeostasis, voluntary movement, and perception, behaviour and memory.
Parts of the body associated with the CNS.
Brain, spinal cord, optic nerve.
What part of the body is associated with the PNS? Name the two divisions.
Nervous tissue outside the CNS.
Sensory/afferent division: info to CNS.
Motor / efferent division: info from CNS to organs.
What are the 4 functions of neuroglia (in general)?
Phagocytosis, nutrient supply for neurons, interstitial fluid, structure and repair of nerve tissue.
What is the function of a Schwann cell?
Forms an insulating myelin sheath around axons, supports non-myelinated axons.
What does a satellite cell do?
Surrounds neuron cell bodies, support and fluid exchange.
What is the function of an astrocyte?
Support (microfilaments) and repair (scar). Communicate with neurons via gliotransmitters, maintain the environment around a neuron, maintains the BBB via endothelium - wraps around vessels to influence their permeability.
What are the features and functions of oligodendrocytes?
They can milinate more than one axon.
Insulating myelin shealth around CNS axons, accelerate action potential.
What is an insulating myelin sheath?
Protein lipid layer.
What is the one function of microglia?
Protection: Phagocytic (macrophages).
What do ependymal cells produce and what are all their features?
Produce cerebrospinal fluid (CFS) which is a mechanical buffer.
Single layer, Cuboidal.
Line the CSF-filled ventricles in the brain and the central canal of the spinal cord.
Cilia to move CSF along brain and microvilli to sample the CSF.
3 basic features of neurons.
Don’t divide, high metabolic rate, conscious and unconscious control.
How does a neuron work?
Branches dendrites send impulses via an action potential through the cell body. One axon sends them to another place.
What are the features of anaxonic neurons and where are they found?
Can’t distinguish dendrites from axons.
Brain, special sense organs.
