Term
| Describe the series of events that occur to cause muscle excitation. |
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Definition
An action potential in a motor neuron makes a synapse with the muscle fiber.
That synapse releases the neurotransmitter acetylcholine which depolarizes the muscle and causes it to produce an action potential.
The action potentials travel to the interior of the muscle fiber along infoldings of the plasma membrane called transverse (T) tubules. this causes the sarcoplasmic reticulum to release Ca2+. The calcium ions result in movement of troponin and tropomyosin on their thin filaments, and this enables the myosin molecule heads to "grab and swivel" their way along the thin filament. This is the driving force of muscle contraction. |
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Term
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Definition
| connect striated cells of the cardiac muscle |
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Term
| What type of muscle can generate action potentials without neural input? |
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Definition
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Term
| Where is Smooth muscle typically found? |
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Definition
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Term
| Stimulation from neurons in what system can cause smooth muscle to contract? |
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Definition
| the autonomic nervous system |
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Term
| What characteristics does the Skeletal muscle have that the smooth muscle does not? |
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Definition
sarcomeres
actin&myosin organized into thin and thick filaments |
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Term
| In smooth muscle, how is contraction controlled? |
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Definition
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Term
| Actin&Myosin in smooth muscle vs. in striated muscle |
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Definition
smooth muscle actin and striated muscle actin are the same
Smooth muscle myosin is different than striated muscle myosin
- smooth muscle myosin will not interact with actin unless activated by phosphorylation |
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Term
| The activation of myosin interacting with myosin requires phosphorylation. What enzyme is required for phosphorylation to occur? |
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Definition
| Myosin Light Chain Kinase (MLCK) |
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Term
| What activates the enzyme MLCK? |
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Definition
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Term
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Definition
a category of ways in which cells interact, there are 4 types
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Term
| What connects the cytoplasm of one cell to the cytoplasm of another cell ? |
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Definition
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Term
| What is the functional whole that is the connection of cytoplasm in plants? |
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Definition
the symplast
The symplast of a plant is the inner side of the plasma membrane in which water (and low-molecular solutes) can freely diffuse. |
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Term
| What is the function of junctions in relation to basal lamina? |
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Definition
| The basal lamina are attached to cells and attached to each other, the junctions prevent stuff from going down in between them. |
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Term
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Definition
| hold cells close together and stop stuff from squeezing between them |
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Term
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Definition
anchoring junctions, join intermediate filaments in one cell to those in a neighbor.
Cadherin protein joins through the membrane into a plate of anchor protein and then keratin filaments are anchored to the filaments in another cell |
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Term
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Definition
| similar to a plasmodesma , have a tube of cytoplasm called connexons that make an open channel between adjacent cells |
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Term
| What are junctions created by? |
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Definition
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Term
| All cells have a ring of _____ around them to prevent unwanted things from getting in. |
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Definition
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Term
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Definition
| a protein called cadherins joins actin of one cell to an actin bundle in another cell |
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Term
| Why shouldn't you pick up a cone snail? |
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Definition
they are neurotoxic
It can paralyze small invertebrates in less than on second so that it can't transmit nerve impulses
-This type of toxin can be used for different medical things like Alzheimer's, parkinsons', epilepsy or pain relief
- 1000 times more effective than morphine! |
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Term
| What type of signals do neurons use to communicate? |
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Definition
electrical - to travel long distance, to ganglia, to your fingers to type
or
chemical - at synapses electrical turns to chemical |
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Term
| Plant cells have an extracellular structure made of cellulose fibers embedded in other polysaccharides and protein. What type of structure do animal cells have instead? |
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Definition
| an elaborate matrix called the extracellular matrix which is made up of glycoproteins and other macromolecules |
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Term
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Definition
| A fibroblast is a type of cell that synthesizes the extracellular matrix and collagen, the structural framework for animal tissues, and plays a critical role in wound healing. Fibroblasts are the most common cells of connective tissue in animals. |
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Term
| Where do you find a lot of ganglia in humans? |
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Definition
| around the spinal column and brain |
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Term
| Instead of having a brain, insects have what? |
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Definition
| a collection of ganglia...which are a collection of neurons |
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Term
| Describe where you'd find sensory neurons, and how sensory information is acquired and travels. |
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Definition
Find them in eyes, ears, nose, fingertips... and they detect what is going on outside
Sensory information is picked up, turned into electrical impulse and travels along as a sensory neuron, goes to the brain then interneurons inegrate the information and the motor output leaves the brain or ganglia via motor neurons which react to the sensory information |
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Term
| Where do you find motor neurons? |
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Definition
| in the peripheral nervous system |
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Term
| What happens to signals at the synapse? |
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Definition
| electrical signals become chemical signals |
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Term
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Definition
| a junction between an axon and another cell |
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Term
| What to the vesicles in synaptical terminals contain? |
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Definition
| neurotransmitters such as amino acids |
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Term
End of an axon is a _____ cell (one with the vesicles), they release their info to a ________(like a muscle or gland)
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Definition
| pre-synaptic, post-synaptic |
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Term
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Definition
| A wave of destruction of the membrane potential |
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Term
| When you depolarize the membrane, what happens to the gated ion channels? |
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Definition
| getting rid of the charge imbalance causes the gate to open, after a while it gets tired and the lid closes, making it inactivated to they have returned to their normal resting phase |
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Term
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Definition
| A particular threshold voltage has to be reached in order for an action potential will occur |
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Term
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Definition
| signals that carry info along axons |
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Term
| The ____ of action potentials reflect the strength of a stimulus. |
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Definition
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Term
| What occurs during the rising phase? |
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Definition
| the threshold is crossed and the membrane potential decreases |
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Term
| What occurs during the falling phase? |
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Definition
| the voltage gated sodium channels become inactivated, the voltage gated potassium channels open and potassium flows out of the cell |
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Term
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Definition
| occurs after an action potential, a second action potential can't happen during this time, and there is temporary inactivation of the sodium channels |
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Term
| Describe 5 functions of the extracellular matrix |
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Definition
Support
Adhesion
Movement
Regulation
communication |
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