Question | Answer |
Muscle Cells | Muscle Fibers |
Contractility | The ability of skeletal muscle to shorten with force. |
Excitability | The ability to be stretched. |
Elasticity | The Ability to recoil to their original resting length after they have been stretched. |
Epimysium | The fibrous tissue envelope that surrounds skeletal muscle. |
Fascia | A connective tissue located outside the epimysium. |
Perimysium | Loose connective tissue. |
Endomysium | Connective Tissue Sheath. |
Myofibrils | A threadlike structure that extends from one end of the fiber to another. |
Actin Myofilaments | Thin myofilaments that resemble 2 minute strands of pearls twisted together. |
Myosin Myofilaments | Thick myofilaments that resemble bundles of minute golf clubs. |
Sarcomeres | Highly ordered units formed by actin and myosin, which are joined end to end to form myofibril. |
Resting membrane Potential | The charge difference across the membrane. |
Action Potential | The brief reversal back of charge. |
Motor Neurons | Nerve cells that carry action potentials to skeletal muscle fibers. |
Neuromuscular Junction | A chemical synapse formed by the contact between a motor neuron and a muscle fiber. |
Synapse | A structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron. |
Motor Unit | A single motor neuron and all the skeletal muscles fibers it innervates. |
Presynaptic Terminal | The enlarged nerve terminal. |
Synaptic Cleft | The space between neurons at a nerve synapse across which a nerve impulse is transmitted by a neurotransmitter. |
Postsynaptic Terminal | The receiving part of the connection between two neurons. |
Synaptic Vesicles | Store various neurotransmitters that are released at the synapse. |
Acetylcholine | A neurotransmitter. |
Acetylcholinesterase | The enzymes that break down acetylcholine. |
Sliding Filament Mechanism | The sliding of actin myofilaments past myosin myofilaments during contraction. |
Muscle Twitch | A contraction of an entire muscle in response to a stimulus that causes the action potential in one or more muscle fibers. |
Threshold | Membrane value. |
All-Or-None Response | The principle that the strength by which a nerve or muscle fiber responds to a stimulus is independent of the strength of the stimulus. |
Lag Phase | The period when the bacteria are adjusting to the environment. |
Contraction Phase | The muscle generates tension. |
Relaxation Phase | The muscle rests. |
Tetany | A condition marked by intermittent muscular spasms, caused by malfunction of the parathyroid glands and a consequent deficiency of calcium. |
Recruitment | The activation of additional motor units to accomplish an increase in contractile strength in a muscle. |
Creatine Phosphate | Phosphorylated creatine molecule that serves as a rapidly mobilizable reserve of high-energy phosphates in skeletal muscle and the brain to recycle adenosine tri phosphate; which is the energy currency of the cell. |
Anaerobic Respiration | The process of producing cellular energy without oxygen. |
Aerobic Respiration | The process of producing cellular energy involving oxygen. |
Oxygen Debt | The amount of oxygen needed to oxidise lactic acid to carbon dioxide and water. |
Muscle fatigue | When ATP is used during muscle contraction faster than it can be produced in the muscle cells. |
Isometric | The length of the muscle does not change, but the amount of tension increases during the contraction phase. |
Isotonic | The amount of tension produced by the muscle is constant during contraction, but the length of the muscle changes. |
Muscle Tone | Constant tension produced by muscles of the body for long periods of time. |
Fast-Twitch Fibers | Contract quickly and fatigue quickly. |
Slow-Twitch Fibers | Contract more slowly and are more resistant to fatigue. |
Origin | Head. The most stationary end of the muscle |
Insertion | The end of the muscle undergoing the greatest movement. |
Belly | The portion of the muscle between the origin and the insertion. |
Synergists | Muscles that work together to accomplish specific movements. |
Antagonists | Muscles that work in opposition to one another. |
Prime Mover | Among a group of synergists, if one muscle plays the major role in accomplishing the desired movement, it is the prime mover. |
Cytoplasm | The material within a cell, excluding the nucleus. |
Z Line | A dark thin protein band to which actin filaments are attached in a striated muscle fiber, marking the boundaries between adjacent sarcomeres. |
A Band | One of the cross striations in striated muscle that contain myosin filaments and appear dark under the light microscope and light in polarized light. |
M Line | In the center of the sarcomere. |
Axons | The long threadlike part of a nerve cell along which impulses are conducted from the cell body to other cells. |
Action Potential | An action potential occurs when the membrane potential of a specific axon location rapidly rises and falls: this depolarisation then causes adjacent locations to similarly depolarise |
Receptor | A protein molecule that receives chemical signals from outside a cell. |
Stimulus | A thing or event that evokes a specific functional reaction. |
H Band | Contains only thick myosin filaments. |
I Band | A light band on each side of the Z line. |
Periods of Inactivity | When muscles aren't active. |
General Principles | What happens in the muscles. |
Attachment | Something attached. |
Nomenclature | The naming of things. |
Cytoplasm | What is inside the cell. |
Structure | What makes up things. |
Membrane Potential | It's potential at rest. |
Nerve Supply | The amount of nerves. |
Synaptic Vehicles | Store various neurotransmitters that are released at the synapse. |
Occipitofrontalis | Raises the eyebrows. |
Orbicularis Oculi | Closes the eyelids and causes "crow's feet" wrinkles in the skin at the lateral corners of the eye. |
Muscle Contraction | The muscles reactions. |
Obicularis Oris | Puckers the lips. |
Buccinator | Flattens the cheek's/ Trumpeter's muscle. |
Zygomaticus | Smiling muscle. |
Levator Labii Superioris | Sneering. |
Depressor Anguli Oris | Frowning. |