Question | Answer |
Neurons | Nerve cells |
Cell Theory | All plants consised of small individual units called cells. 1838 |
What is the cell body called? | Soma |
What are the branches of neuron called? | Neurites |
Axon | the neurite that convey info away usally the biggest |
Dendrites | conveys info towards the cell body |
Synapses | Where one neuron comes close or touches another and where communication between one neuron and another takes place |
Synaptic Transmission | The mechanism causes the process of communication |
name two ways neurons are classified? | What a neuron does and what a neuron looks like. |
Name the types of neurons when classifying them with what they do? | Sensory neurons, moter neurons, and interneurons (neurons who decide or neurons located in the brain or spinal cord) |
Name the types of neurons when clssifying them with what they look like? | Anaxonal, Monopolar, Bipolar, Multipolar |
How many ways do neurons communicate and what are they? | Two: Chemcial and electrical |
What is the neuron that sends the message called? | Presynaptic neurons |
what is the neuron that receives the message called? | postsynaptic neurons |
What is a Synaptic cleft? | The small gap between neurons |
What is the differents between chemical and electrical synapses? | chemical has a small synaptic cleft while electrical touches, chemical uses synaptic vesicles in the presynaptic terminals electric doesn't, chemical is polarized communication (can only go in one direction) electrical goes both ways. |
What is a reciprocul synapses? | two chemical synapses immediately adjacent to one another with one transmitting info one way and the other the other way. |
Glia or neuroglia cells are? | non-neural |
What are the 4 types of glia? | Astroglia, Microglia, Oligodendroglia, and Schwann cells |
Which glia are only found in the brain and spinal cord? | Astroglia, Microglia, Oligodendroglia |
Which glia are only found in the peripheral nerves? | Schwann cells |
What do Astrocytes do? | provide physical support for neurons and help regulate the extracellular concentration of potassium ions. They also may play a role in neuronal communication. |
What do Microglial do? | Seem to have a defensive function by consuming cellular debris stemming from injury or disease. |
What is different about Microglial than other glia? | They develop from mesodermal rather than ectodermal tissue. |
What is Myelin? | a membrane that is wrapped tightly several times around most axons and long dendrites in the nervous system. |
What is the color of Myelin? | Shiny white |
What does Myelin do? | acts as a electrical insulator to increase the speed of conduction of nerve impulses. |
What is a Node of Ranvier? | the gap that seporates myelin bundles from each other. |
What are the two glia that form myelin? | Schwann and oligodendrocytes |
What is the cell membrane of a neuron mostly composed of? | Phospholipids and proteins |
What does phospholipids consist of? | hydrophilic(water seeking)the head and hydrophobic(water avoiding)fatty acid tails |
What does the phospholipids do in the membrane? | it makes the membrane impermeable to ions and allows proteins to move around. |
What does the movement of proteins do for the cells? | it allows the cell to respond to external chemical signals |
What is the membrane referred to? | the lipid bilayer |
What percent of the membrane is protein? | 20% |
What part of the membrane of a typical neuron confers many of it's characteristics that distinguish it from other types of cells? | the protein |
How does a neuron change it's own functional characteristics? | by changing the types of proteins it contains |
What are the types of proteins are there? | transport, signaling, and miscellaneous(binding) |
What do Transport Proteins do? | it allows or facilitate the movement of water, water-soluble ions, and other substances into or out of the cell |
what do Signaling Proteins do? | they receive or espond to chemical messages coming from outside the neuron |
What do Binding Proteins do? | they help bind cells to one another or to an extra cellular matrix of molecules that is present around some cells. |
What are Transport Proteins made of? | Ion Channel, Ion pump, and other transporters |
What is an Ion Channel? | it allows the passive flow of ions through the membrane. |
What is an Ion Pump? | expends energy to move one or more ions across the membrane against a concentration gradient |
What are Signaling roteins mostly made up of? | Receptors, G Protein, Other enzymes |
What are Receptors? | Binds with a signaling molecule and initiates the neuron's response |
What are G Protiens? | Initiates a cascade of biochemical reactions that leads to a neuron's response to a signaling molecule. |
What are Binding Proteins mostly made up of? | Adhesion Proteins and Cytoskeletal Binding Proteins |
What are Adhesion Proteins? | They anchor the neuron to other cells |
What are Cytoskeletal Binding Proteins? | They anchor the cell membrane to internal cytoskeleton |
What do Ion Channels look like? | They are cylindrical with a central core through which the ions flow. |
How large are the typical Ion channels? | 0.3 to 0.6nm in diameter |
What are the chemically similar subunits of an ordinary ion channel made up of? | Transmembrane domains |
What are Transmembrane Domains? | they are helical strands that cross the membrane of the cell |
What are Transmembrane Domains connected by? | Amino Acids |
What confers the Channel it's specific properties? | The Amino Acids |
What are the types of ways that ions can move through a channel? | Leakage Channels and Gated Channels |
What is a Leakage Channel? | ion channels that are open to the flow of ions all the time. |
What are Gated Channels | they open and close. |
how do the Gated Channels open and close? | a charge in the structure of the channel protein called conformational charge. |
What is a Conformational Charge? | it opens and closes the gate of the channel. |
Can channels have more than one gate? | yes |
What are the types of Gates? | Ligand-gated channel or ligand-sensitive channel, voltage-gated channel or voltage-sensitive channel, and stretch-sensitive channel |
How does the Ligand-Gated Channel or Ligand-Sensitive Channle open and close? | The presence of a particular kind of signaling molecule by opening and closing only in the presence of it. |
How does the Voltage-Gated Channel or Voltage-Sensitive Channel opne and close? | regulated by the difference in electrical potential across the neuronal membrane |
How does the Stretch-Sensitive Channel open and close? | When a mechanical force is applied to it. |
What are Connexons? | a specialized channel that forms gap junctions |
How many Connexons are typically i a synapse? | as many as 100 tightly packed pairs |
What do the tightly packed connexons do? | They connect the interiors of two adjacent neurons |
What are the Connexons made up of? | 6 parts called Connexins |
What do the Connexins do? | they twist to open and close the central pore. |
What makes the Connexins do what they do? | the presence or absence of specific chemical signals |