Test 1 Flashcards
Receive and transmit info to other cells
Neurons
Play supportive role in brain functioning
Gila cells (neuroglia)
Spaniard Santiago Ramon y Cajal
Demonstrate individual cells comprising nervous system remained separate
Two layers of fat molecules
Most chemicals restricted from flowing in and out of neurons
Cell membrane (plasma membrane)
Membrane enclosed structure within cell
Contains DNA
Cell nucleus
Site of protein synthesis in cell
Ribosomes
Provide cell with energy
Requires oxygen to function
Mitochondrion
Transports newly synthesized protein to destination
Endoplasmic reticulum
Conduct impulses to muscles and glands from spinal cord
Motor neuron
Contains nucleus, ribosomes, mitochondria
Cell body (soma)
Sensitive to certain types of stimulation (light, touch, smell, taste, sound)
Sensory neuron
Long thin fiber sending electrical impulse to other neuron, muscles, and glands
Axon
Insulating material covering some neurons
Myelin sheath
Branches extend from cell body receiving information from other neurons
Dendrites
Swelling at tip of axon
Releases chemicals
Presynaptic terminal (bouton or end bulb)
Bring info to a structure
Afferent axons
Sending info away from structure
Efferent axons
Entirely located within single structure of nervous system
Intrinsic neurons (interneurons)
Characteristics of axon
Take into away from cell body Smooth surface Generally 1 axon per cell No ribosomes Canhave myelin branch furtherfrom cell body
Characteristics of dendrites
Bring info to cell body Rough surface Usually many dendrites per cell Have ribosomes No myelin insulation Branch near cell body
Structure of neuron
Variations
Function related to shape
Shape is plastic
Build myelin sheath around one axon in peripheral nerve
Schwann cells
Type of astrocyte
Guides migration of neurons, axon, and dendrites growth
Radial glia
Help synchronize activity of axon by wrapping around presynaptic terminal
Astrocytes
Remove waste material, viruses, and fungi from brain
Microglia
Build myelin sheaths around multiple axons in brain and spinal cord
Oligodendrocytes
Nourishment of vertebrate neurons
Glucose
Amino acids
Thiamine
Oxygen
Difference in electrical potential or voltage
Resting potential
Electrical message transmitted down axon of neuron
Nerve impulse
Difference in distribution of ions between inside and outside of membrane
Concentration gradient
Semi permeable capillaries that keep most chemical out of vertebrate brain
Blood brain barrier
Resting potential
Neuron maintains electrical polarization
-70 millivolts
Allows neuron to respond quickly to a stimulus
Electrical message transmitted down axon of neuron
Nerve impulse
Difference in distribution of ions between inside and outside of membrane
Concentration gradient
Increasing polarization or difference between electrical charge of two places
Hyperpolarization
Decreasing polarization towards zero
Depolarization
Protein mechanism found along neuron membrane which transports sodium ions outside while drawing potassium ions into cell
Sodium potassium pump
Difference in positive and negative charges across membrane
Electrical gradient
