What are the general functions of Muscles?
What are the characteristics of Muscle tissues?
What is the ability of the muscle to be stimulated (respond to nerve impulses)?
What is the ability of the muscle to contract or shorten?
What is the ability of the muscle to extend or stretch?
What is the plasma membrane of muscle fiber?
What is the cytoplasm of the muscle fiber?
What organelle is the "powerhouse of the cell"?
Muscle cells are called fibers because of what?
Their threadlike shape
What is the network of tubules and sacs found within muscle fibers that temporarily stores Ca ions?
Sarcoplasmic Reticulum (SR)
What part of the muscle cell temporarily stores Ca ions?
What extend transversely across the sarcoplasm at right angles to long axis of muscle fiber formed by inward extensions of sarcolemma?
What allow electrical signals, or impulses traveling along the sarcolemma to move deeper into the cell?
What is a triplet of tubules; a T tubule sandwiched between two sacs of sarcoplasmic reticulum?
What allows the electrical impulse traveling along a T Tubule to stimulate the membranes of adjacent sacs of the Sarcoplasmic Reticulum?
What are the bundles of very fine cytoskeletal filaments that extend lengthwise along skeletal muscle fiber and almost fill the sarcoplasm?
What are the fine fibers that make up Myofibrils?
What are the two types of Myofilaments?
What are the protiens that make up the thick Myofilaments?
What are the protiens that make up the thin Myofilaments?
What is the basic contractile unit of the muscle cell?
What is located in the middle of the thin Myofilament?
Z Line (Z disk)
What is a segment of the myofibril between two sucessive Z lines?
What is the segment of sarcomere that runs the entire length of the thick filaments?
What is the segment of sacromere that includes the Z line and ends of the thin filaments where they don't overlap the thick filaments?
What is another name for muscle?
Each myofibril consists of approximately how many sarcomeres?
What does myosin make up?
What protein is chemically attracted to the Actin?
What is the area where the Myosin "heads" are attached to actin?
What is the globular protein that forms two fibrous strands that twist around each other to form the bulk of thin filament?
What protein blocks the active sites on the Actin molecules?
What protein holds the tropomyosin molecules in place?
What part of the Myosin is atracted (towards) the Actin?
What binds with Troponin which causes the troponin to release the tropomyosin?
When does contraction begin?
When Ca++ binds to Troponin
Skeletal muscle fiber remains at rest until stimulated by what?
What is the special type of nerve cell that stimulates skeletal muscle fibers?
Where do Motor Neuron's connect?
To the Sarcolemma of a muscle fiber at a folded motor endplate
What is the area where the motor neurons connect to the carcolemma at the motor endplate?
What is the junction where the motor neuron connects to the sarcolemma of a muscle fiber at a folded motor endplate?
Neuromuscular Junction (NMJ)
What is the neurotransmitter that is released into the synaptic cleft that diffuses across gap, stimulates receptros, and initiates impulse in sarcolemma?
Nerve impulses travels over the Sarcolemma and inward along what?
What releases the calcium ions from the SR?
The nerve impulses that traveled along the sacrolemma and inward along the T tubules
What binds to Troponin causing Tropomyosin to shift and expose active sites on Actin?
What happens when the active sites on actin are exposed?
Myosin heads bind to the Actin
What is it called when the thick filaments pull on the thin filaments?
Sliding filament model
Muscle fibers usually contract how much of their starting length??
What happens when Ca++ ions are removed from troponin molecules?
Shuts down contraction
Where do Ca++ ions go when released from the troponin molecules?
Ca++ ions are pumped back into the sacks of the Sarcoplasmic Reticulum
What are the 2 types of energy sources muscle uses for contraction?
There is only enough ATP in muscle fiber for how long of maximum contraction?
What is the backup energy supply for ATP?
How much additional energy does Creatine Phosphate provide for maximal contraction?
20 additional seconds
Muscle fibers continually resynthesize ATP from the breakdown of what?
Where does ATP bind to transfer it's energy to perform the work of pullin thin filament during contraction?
Muscle fibers ensure an uninterrupted supply of glucose by storing it in the form of what?
What is the catabolic process that produces the maximum amount of energy available from each glucose molicule?
Where does the lactic acid return to out of the blood?
the Liver and is converted back into glucose
Anaerobic respiration results in the formation of what?
What gives Myoglobin it's reddish pigmentation?
What muscle fibers have high levels of myoglobin
What muscle fibers have little myoglobin?
What are the 3 different types of skeletal muscle fibers that can be classified according to their structural and functional characteristics?
Red fibers- Slow
White fibers- Fast
At rest excess O2 in the sarcoplasm is bound to what?
What type of respiration occurs when low levels of O2 are available and results in the formation of lactic acid?
What type of respiration occurs when adequate O2 is available?
What is the functional unit that consists of a Motor neuron plus the muscle fibers to which it attaches?
What type of motor neuron forms that motor unit with a muscle fiber?
Somatic Motor Neuron
One single contraction is called what?
A twitch Contraction
What are the 3 phases of the twitch contraction?
Each twitch contraction usually lasts how long?
Less than 1/10 of a second
A series of twitch contractions or "staircase phenomenon" is called what?
What is the gradual steplike increase in the strength of contractions seen in a series of twitch contractions that occur 1 second apart?
Treppe (staircase phenomenon)
What benifits do you get from warming up muscle fibers?
-Calcium ions diffuse through the SR more efficiently
-More actin-myosin reactions occur
What is a smooth, sustained contraction called?
What is caused by any combination of local failure in the steps of muscle contraction?
Physiological Muscle Fatigue
What are 3 things that cause Physiological Muscle Fatigue
-Lack of ATP
-Depletion of O2 or Glucose
-Build up of Lactic Acid
What is the continual, partial contraction of a muscle?
Muscles with less tone than normal are?
Muscles with more tone than normal are?
What is the principle that skeletal muscles contract with varying degrees of strength at different times?
Graded Strength Principle
When is the strongest maximal contraction possible?
Only when the muscle organ has been stretched to it's optimal initial length
The maximal strength that a muscle can develope bears a direct relationship to what?
Length of it's fibers
What is the response in which the body tries to maintain constancy of muscle length in response to increased load?
What are the two different type of muscle contractions?
What type of contraction is a contraction in which the tone or tension within a muscle remains the same as the length of the muscle changes?
What does Isotonic mean?
What type of contraction is a contraction in which muscle lenth remains the same while the muscle tension increases?
What are the two types of Isotonic contraction?
What type of isotonic contraction is when the muscle shortens as it contracts?
What type of isotonic contraction is when muscle lengthens while contracting?
What are painful muscle spasms?
What are minor traumas to the body that may cause a muscle bruise?
What is an injury to skeletal muscles caused by overexertion or trauma called?
What is an injury to a ligament refered as?
What are the three types of muscle tissue?
What type of muscle tissues are voluntary?
What type of muscle tissues are involuntary?
What type of muscle tissue has Striations?
What type of muscle tissue has NO striations?
What type of muscle tissues have many nucleus?
What type of muscle tissues are characterized by having a single nucleus?
What type of muscle tissues have narrow T Tubules that form triads with the SR?
What type of muscle tissues have large diameter T Tubules that form diads with the SR and regulate Ca++ entry into the sarcoplasm?
What type of muscle tissues have no T Tubules?
What type of muscle tissue has a very poorly developed sarcoplasmic reticulum?
What type of muscle tissue has a extensive Sarcoplasmic Reticulum that stores and releases Ca++?
What type of muscle tissue has a sarcoplasmic reticulum that is less extensive than in skeletal muscle?
What type of muscle tissue has no gap junctions?
What type of muscle tissue has cell junctions of intercalated disks?
What type of muscle tissue has many gap junctions?