The Muscle Tissue Flashcards
Give me the 3 general characteristics of a muscular tissue.
- It consists of elongated cells
- It is surrounded by connective tissues which conveys blood vessels, nerves, and lymphatic’s throughout the muscle.
- It is specialized for contraction
What do you call the slight interaction of myosin filaments and actin filaments?
Contraction
All muscle cells are derived from the?
Mesodermal Origin
Enumerate the 3 main cells in muscular tissue.
- Myoepithelial cells
- Pericytes
- Myofibroblasts
It is an important component of secretory glands where they function to expel secretions from the glandular.
Myoepithelial cells
What do you call the smooth muscle cell that surrounds blood vessels?
Pericytes
What do you call the cells that has contractile functions and secretes collagen?
Myofibroblasts
What is the process of producing heat?
Thermogenesis
What are the 3 different types of muscle tissue?
- Skeletal muscle
- Cardiac muscle
- Smooth muscle
Give me the general characteristics of skeletal muscle tissue.
- It has long, cylindrical, striated fibers.
- multinucleated cell with nuclei at the periphery
- voluntary
Where is the location of skeletal muscle tissue?
It is usually attached to bones by tendons
What are the 4 functions of skeletal muscle tissues?
- motion
- posture
- heat production
- protection
Skeletal muscle cell/fiber
What do you call the tiny invagination that panels in from the surface towards the center of the cell?
Transverse tubule
Skeletal muscle cell/fiber
What do you call the membranous sac that encircle each of the myofibrils?
Sarcoplasmic Reticulum
What does sarcoplasmic reticulum stores?
Calcium (Ca) and Iron(Fe)
Skeletal muscle cell/fiber
It is used in the synthesis of ATP
Glycogen granules and Mitochondrion
Skeletal muscle cell/fiber
What do you call the contractile organelles?
Myofibrils
Skeletal muscle cell/fiber
Myofibrils are characterized by the presence of myofilaments. What are those myofilaments?
Actin and Myosin
What myofilament has 8 nm in diameter and 1-2 microns in length? (thin)
Actin
What myofilament has 16 nm in diameter and 1-2 microns in length? (thick)
Myosin
Myofilaments are arranged in compartments called ______________. It is the functional unit of myofibril.
Sarcomeres
What is the cell membrane surrounding a skeletal muscle fiber/ cell?
Sarcolemma
What do you call the cytoplasm of striated cells?
Sarcoplasm
It is a narrow region of dense materials that separates the sarcomere to another.
Z disc
It is a dark middle part that extends to the entire length of thick filaments.
A band
It is lighter, less dense, are of the sarcomere that contains the remainder of thin filaments.
I band
It is a narrow region in the center of each A band. It contains thick filaments
H - zone
It is a region in the center of the H-zone that contains proteins which holds the thick filaments together at the center of the sarcomere.
M line
What are the 3 types of muscle proteins?
- Contractile Proteins
- Regulatory Proteins
- Structural Proteins
What muscle protein generates force during muscle contraction?
Contractile Proteins
Myosin molecules consists of a _______ and __________. This will bind to myosin binding sites on the actin molecules during muscle contraction.
1 tail
2 myosin heads
Myosin molecules consists of a _______ and __________. This will bind to myosin binding sites on the actin molecules during muscle contraction.
1 tail
2 myosin heads
Each actin molecule has a _____________ where the myosin tail and head will bind.
myosin binding site
What muscle protein helps switch muscle contraction ON and OFF?
Regulatory Protein
What are the 2 types of regulatory protein?
1.Tropomyosin
2. Troponin
Explain the mechanisms of Tropomyosin and Troponin
Tropomyosin (OFF)
- when skeletal muscle fiber is relaxed, tropomyosin will cover the myosin binding sites on the actin molecules, thereby preventing myosin to bind with actin.
Troponin (ON)
- when troponin binds to calcium, it changes shape, it moves the tropomyosin away from myosin binding sites thereby producing muscle contraction.
Give the 3 functions of structural protein
- For the proper alignment of thick and thin filaments
- It provides elasticity and extensibility
- It links myofibrils to sarcolemma and extracellular matrix
Give the 5 types of structural proteins
- Titin
- a-Actinin
- Myomesin
- Nebulin
- Dystrophin
What structural protein connects the Z disc to M line?
It also stabilizes __________________ position and can stretch and then spring back.
Titin
What structural protein attaches to actin molecules of thin filaments and titin molecules? (It is the structural protein of Z disc)
a-Actinin
What structural protein binds to titin molecules and connects adjacent thick filaments to one another? (It is the structural protein of M line)
Myomesin
What structural protein wraps around the entire length of each titin filament and helps anchor thin filaments to Z disc? It also regulates length of thin filaments during development.
Nebulin
What structural protein links thin filaments of sarcomere to integral proteins in sarcolemma? It reinforces sarcolemma and helps transmit tension generated by sarcomeres to tendons.
Dystrohin
What is the levels of organization of a skeletal muscle? (5)
Filaments (myofilaments) - Myofibril - Muscle Fiber/Cell (covered by endomysium) - Muscle Fascicle (wrapped in perimysium) - Skeletal muscle (wrapped in epimysium)
What is the levels of organization of a skeletal muscle? (5)
