TEST 2- Anatomy 1 Flashcards
Functions of Muscular Tissue?
- Contractile
- Extensible
- Elastic
What are muscle tissue main functions?
- Create motion
- Stabilize body maintain posture
- Store substances using sphincters
- Move substances peristaltic contractions
- Generate heat, thermogenesis
Three types of muscular tissue with appearance and control?
- Skeletal-striated multi nucleated/voluntary
- Cardiac- striated one central nucleus/involuntary
- Visceral smooth muscle- no striations one central nucleus/involuntary
Organizational structure
- Entire organ
- Single muscle cell
- A bundle of muscle fibers or bundle of muscle cells
- Organelle in a muscle fiber composed of filaments
- Fibrous protein molecules within myofibrils
- Muscle
- Fiber
- Fascicles
- Myofibril
- Filaments
Connective Tissue
- Surrounds a fiber
- Surrounds a fascicle
- Surrounds entire muscle
- Endomysium
- Perimysium
- Epimysium
Nerve Supply
- Nerve cell called ______ supplies a group of muscle fibers. This comprises a motor unit
- Each muscle fiber is supplied by __________?
- The site where neuron contacts muscle fiber.
- Somatic neuron
- One Neuron
- Neuromuscular Junction
Microscopic Organization of skeletal muscle
- During embryonic development, a number of _______ fuse to form one skeletal muscle fiber
- Skeletal muscle fibers are ________
- The resultant cell (muscle fiber) is unable to undergo _______
- Myoblast
- Multinucleate
- Mitosis
The skeletal muscle fiber
- Beneath the connective tissue Endomysium is found the ____________ of an individual skeletal muscle fiber
- The ____________ of skeletal muscle fibers is chocked full of contractile proteins arranged in myofibrils
- Plasma membrane (called sarcolemma)
2. Cytoplasm (sarcoplasm)
Microscopic organization of skeletal muscle
- Kind of like a culdesac opening from outside of the fiber toward interior of fiber
- opening invaginate from sarcolemma, and extend toward the interior of the cell
- Open to outside of the fiber, so they are filled with interstitial fluid
- IMPORTANT IN PROPAGATION OF MUSCLE ACTION POTENTIALS
- T-tulles (Transverse tubules)
Microscopic Organization of Skeletal muscle
- Stores calcium ions, and releases them when the muscle fiber is stimulated
- Sarcoplasmic Reticulum
Microscopic Organization of Skeletal Muscle
- Dilated regions that flank the T-Tubules
- Two Terminal cisterns flanking one T-Tubule is called a _______
- Terminal cisterns
2. Triad
The Skeletal Muscle Fiber
- The basic functional unit of skeletal muscle fibers is the _________. An arrangement of thick and thin filaments sandwiched between two Z disk
- Sarcomere
Filaments
- Myofibrils are made of smaller structures called _________?
- Overall, there are _________ filaments for every __________ filament
- Thin Filaments contain ________, ________, _______
- Thick Filaments contain ________, ________
- Filaments
- Two thin/One thick
- Actin, Troponin, Tropomyosin
- Myosin, Contractile protein
- Filaments inside a myofibril are arranged in compartments and are the basic functional units of a myofibril. This is known as __________
- Long chain of Sarcomeres is a _________
- Sarcomeres
2. Myofibril
Sarcomeres
- Thick and thin filaments create the striations that are seen both in _________ and whole __________
- Myofibrils/Muscle Fibers
Sarcomeres
- Thick and thin filaments overlap to a degree causing
- _________: Where adjacent Sarcomeres abut; center of an I band
- _________: Darker zone, comprises length of thick filaments and varying overlap of thin filaments
- _________: Thin Filaments, consist of parts of 2 adjacent Sarcomeres
- _________: Center of an A band, only thick filaments
- _________: Midline of a sarcomere
- Z disk
- A band
- I band
- H zone
- M line
Fine Structure
- Thick filament is composed of _________
- The tails of the myosin molecules are bound together to form the __________
- Myosin molecules
2. Thick filament
Fine Structure
The heads (crossbridges) of the myosin molecules
- ______ and _______ ATP; also bind the products ADP and Phosphate
- Change shape moving ______ or ________
- Bind _______ to Actin
- Bind/ Hydrolyze
- Toward/ Away from an M line
- Reversibly
Muscle Proteins
- The Regulatory proteins _______ and ________ are myosin binding sites that are covered
- Troponin and tropomyosin
Fine Structure
- Movement of the ______ and _______ complex allows contraction to begin
- Movement is triggered by ________ binding to troponin
- Troponin/Tropomyosin
2. Calcium
Fine Structure
- Muscle Fiber proteins comprise three categories:
- Contractile proteins: Myosin, Actin
- Regulatory proteins: Troponin, Tropomyosin
- Structural proteins: Titin, Myomesin, Dystrophin, Sarcolemmal proteins
Fine Structure
Structural Proteins:
- _____: each molecule spans half a sarcomere, from a Z disc to an M line, and attaches thick filaments to Z discs and M lines.
- Very elastic and probably helps sarcomere return to its resting length
- Titin
Fine Structure
- _______: Links the thin filaments of the Sarcomeres to integral membrane proteins in the sarcolemma, transmitting the tens I’ve forces of the Sarcomeres
- Dystrophin
Muscular Dystrophy
- Muscular refers to group of inherited muscle destroying diseases causing progressive skeletal muscle fiber degeneration, the most common from being ___________
- Absent the reinforcing effect of ________, the sarcolemma tears easily during muscle contraction, causing muscle fibers to rupture and die
- Duchesse Muscular Dystrophy
2. Dystrophin
Generation of an Action Potential
- Recall that each muscle fiber is supplied by _______
- Each muscle fiber has one ________
- _________ is where a muscle action potential is generated, the signal for a muscle to contract
- Muscle action potential travels along the ________ and down the _______ to the interior of the _______
- Somatic motor neuron
- Neuromuscular junction
- Neuromuscular junction
- Sarcolemma/T-tubles/Fiber