Term
| Three types of muscles tissue are: |
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Definition
| skeletal, cardiac, and smooth |
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Definition
| Skeletal and smooth muscle cells |
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Definition
| Two kinds of myofilaments that muscle contraction depends on |
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Definition
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Definition
| Cytoplasm of a muscle cell |
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Definition
| Prefixes that all refer to muscle |
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| Skeletal muscles are responsible for: |
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Definition
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| Cardiac muscle is responsible for: |
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Definition
| ...coursing the blood through the body |
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| Smooth muscle helps maintain: |
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Definition
| ...blood pressure, and squeezes or propels substances (i.e. food, feces) through organs |
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| Excitability or irritability |
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Definition
| The ability to recieve and respond to stimuli |
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Definition
| The ability to shorten forcibly |
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Definition
| The ability to be stretched or extended |
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Definition
| The ability to recoil and resume the original resting length |
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Definition
| Fine sheath of connective tissue composed of reticular fibers surrounding each muscle fiber.
[image] |
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Definition
| Fibrous connective tissue that surrounds groups of muscle fibers called fascicles
[image] |
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Definition
| An overcoat of dense regular connective tissue that surrounds the entire muscle
[image] |
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Definition
| Elongated cell
Multiple peripheral nuclei
Visible striations
Voluntary
[image] |
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Definition
| Branching cell
Single central nucleus
Visible striations
Involuntary
[image] |
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Definition
| Spindle-shaped cell
Single central nucleus
Lack visible striations
Involuntary
[image] |
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Term
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Definition
| Extend the entire length of an A band
[image] |
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Term
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Definition
| Extend across the I band and partway into the A band
[image] |
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Definition
| coin shaped sheet of proteins (connectins) that anchors the thin filaments and connects myofibrils to one another
[image] |
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Definition
| A protein present in M lines that makes them appear darker |
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Definition
| Protein that makes up a thick filament. Each myosin molecuole has a rod-like tail and two globular heads
[image] |
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Definition
| Protein that makes up thin filaments.
Each actin molecule is a helical polymer of globular subunits called G actin.
The subunits contain the active sites to which myosin heads attach during contraction
[image] |
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Term
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Definition
| Proteins bound to actin that regulate the interaction of actin and myosin. |
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Term
| Sarcoplasmic Reticulum (SR) |
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Definition
| The endoplasmic reticulum of the muscle cell; its interconnecting tubules surround each myofibril
[image] |
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Definition
| Sac like regions of the sarcolplasmic reticulum that serve as specialized resevoirs for calcium ions.[image] |
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Definition
| Elongated tubes that penetrate into the cell's interior where the A band and I band meet up.
Associated with the paired terminal cisternae to form triads.
Conduct impulses to the deepest regions of the muscle.
These impusles signal for the relase of calcium ions from adajacent terminal cisternae.
[image] |
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Definition
| 3 unit group consisting of one T tubule lying between two adjacent terminal cisternae.
[image] |
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Definition
| The contractile unit of muslce that extends from one Z line to the next.
Includes the entire A band and half of the I band (to the Z line) on each side of the A band.
[image] |
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Definition
| A bundle of muscle cells (fibers) bound together by connective tissue to form a functional unit
[image] |
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Term
| In order to contract a skeletal muscle must: |
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Definition
Be stimulated by a nerve ending
Propagate an electrical current, or action potential, along its sarcolemma
Have a rise in intracellular calcium ion levels, the final trigger for contraction |
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Definition
| The intracellular fluid in which the organelles are suspended |
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Definition
| The cytoplasmic organelle that is the site of ATP synthesis; referred to as the "powerhouse" of the cell[image] |
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Definition
| A cylindrical bundle of contractile filaments within the skeletal muscle cell[image] |
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Definition
| The cellular structure that contains the genetic material of the cell[image] |
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| Whole muscle is surrounded by what connective tissue? |
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Definition
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Term
| A fascicle is surrounded by what connective tissue? |
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Definition
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Term
| A muscle cell (fiber) is surrounded by what connective tissue? |
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Definition
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Term
| Resting Membrane Potential |
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Definition
| The voltage that exists across a cell's plasma membrane when the cell is at rest (not conducting an impulse); cell interior is relatively more negative than the cell exterior. The resting membrane potential is measured in millivolts. |
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Definition
An electrical signal consisting of the depolarization and subsequent repolarization of a nerve or muscle cell membrane.
Travels along the membrane and functions as a signal to initiate an activity (i.e. a muscle contraction) |
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Term
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Definition
| A decrease in the negative resting membrane potential (the voltage that exists across the plasma membrane) |
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Definition
| A single nerve cell that extends from the brain or spinal cord to a muscle or gland |
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Term
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Definition
| The place where a motor neuron stimulates a muscle cell.
The muscle cell and motor neuron do not actually touch, but are separated by the synaptic cleft
[image] |
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Definition
The swollen distal end of an axon.
Contains a neurotransmitter substance within synaptic vesicles |
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Term
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Definition
Membranous organelles containing neurotransmitter substances.
Found within the axon terminals of neurons |
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Term
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Definition
| The neurotransmitter released by a motor neuron at the neoromuscular junction; one of the principal neurotransmitters of the peripheral nervous system |
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Term
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Definition
| The space between the axon terminal and the membrane of the target cell. |
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Definition
Molecules released from synaptic vesciles in neuron axon terminals
Bind to receptor sites on target cells stimulating or inhibiting them |
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Definition
| The bulk transport of material out of the cell by first fusing a membrane-bound vesicle with the plasma membrane. When the membrane ruptures, the contents of the vesicle are released into the extracellular space. |
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Definition
| The process of reproducing and spreading the action potential along the sarcolemma and down the T tubules |
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Term
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Definition
| A condition in which a difference in electrical charge exists across a cell membrane |
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Term
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Definition
| Calcium atoms with two positive charges; concentrated in the extracellular fluid and terminal cisternae, but enter then cytosol where they play an important role in many processes such as muscle contraction and the release of neurotransmitters. |
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Term
| Voltage-regulated calcium channels |
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Definition
| Integral proteins in cell membranes that respond to changes in membrane voltage by changing shape, which opens or closes calcium-specific channels in the proteins. When the channels are open, calcium ions move from one side of the membrane to the other. |
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Definition
| A specific region on a protein to which another molecule become attracted and attaches. Also called a binding site |
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Term
| Chemically regulated ion channels |
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Definition
| Integral proteins in cell membranes that serve as ion channels. When a specific chemical binds to the receptor site on the protein, the protein changes shape, opens the channel and allows certain ions to move from one of the membrane to the other. |
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Definition
| An enzyme located in the synaptic cleft that rapidly degrades the neurotransmitter acetylcholine. In muscle cells, the immediate breakdown of acetylcholine prevents repetitive stimulation of the motor end plate in the absence of action potentials. |
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Term
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Definition
| The period immediately following the transmission of an impulse in a muscle, in which a neuron or muscle cell regains its ability to transmit another impulse |
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Definition
| Refers to the activation of myosin's cross bridges (force generating sites) |
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Term
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Definition
| Occurs when the tension generated by the cross bridges exceeds forces opposing shortening |
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Term
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Definition
| cross bridges become inactive, the tension generated declines, and relaxtion is induced. |
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Term
| The 2 Types of Muscle Contractions Are: |
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Definition
| Isometric and Isotonic contraction |
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Term
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Definition
| Increasing muscle tension (muscle does not shorten during contraction) |
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Term
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Definition
| Decreasing muscle length (muscle shortens during contraction) |
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Term
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Definition
| A motor unit and all of the muscle cells it stimulates
[image] |
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Term
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Definition
| The stimulation of additional motor units to increase strength of contraction |
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Term
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Definition
| A neuron within the brain or spinal cord that lies between sensory and motor neurons. Also called an association neuron. |
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Term
| What is the advantage of having only a few muscle cells per motor unit? |
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Definition
| Generates precise movements |
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Term
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Definition
| Contain few muscles and are found where precise movements are needed. Like in the muscles of the eye. |
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Term
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Definition
| Contain large muscles that exhibit gross movements, such as movements of the thigh, in which a single neuron is connected to a larger number of muscle cells. |
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Definition
| The nearly constant state of low-level tension and resistance to stretch in a muscle |
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Term
| Muscle tone minute contractions are maintained by... |
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Definition
| activities of the spinal cord and result in a firmness of the muscle |
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Term
| If a muscles motor nerve is cut or damaged... |
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Definition
| The muscle loses all tone and will become flaccid (soft and limp; not firm) |
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Term
| 4 Unique Characteristics Of Smooth Muscle |
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Definition
| 1. Smooth muscle tone, 2. slow prolonged contractile activity, 3. Low energy requirements, 4. Response to stretch |
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Term
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Definition
| Fast twitch, fatigue prone fibers. Light in color due to reduced myoglobin. Found in sprinters. |
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Term
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Definition
| Slow twitch oxidative, fatigue resistant fibers. Red due to myoglobin. Found in long distance runners. |
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Term
| Three factors that affect muscle tension: |
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Definition
| 1. Frequency of stimulation, 2. Number of motor units recruited, 3. Degree of muscle stretch |
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Term
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Definition
| A single, rapid contraction in response to a stimulus. |
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Term
| A complete muscle twitch is divided into three phases: |
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Definition
| 1. Latent period, 2. Contraction, 3. Relaxation |
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