Muscle Ultrastructure (Exam 3) Flashcards
What does muscle tissue do?
The basis of all movement and essential biological functions
Contraction and relaxation
Maintain body temperature
Communication
What are some of examples of what muscle tissue is the basis of? (5)
Locomotion Digestion Breathing Vision Circulation
How much of body mass is muscle tissue?
30-40%
What are 3 types of muscle tissue?
Skeletal
Cardiac
Smooth
What is skeletal muscle like?
Voluntary, striated, multinucleated, non-branched
What is cardiac muscle like?
Involuntary, striated, uninucleated, branched
What is smooth muscle like?
Involuntary, non-striated, uninucleated, tapered
What are the differences between the different types of muscle tissues?
Microstructure
How to contract
What is striation caused by?
Organization of protein filaments
If the muscle is highly organized, is it striated or non-striated?
Striated
If the muscle is lacking organized, is it striated or non-striated?
Non-striated
Where is the skeletal muscle originated (origin)?
On one side of the joint
Where is skeletal muscle terminated?
On the other side of the articulation (insertion)
Which end of skeletal muscle moves?
Articulation
What does attachment occur through in skeletal muscle?
Tendon
What is the tendon?
Dense connective tissue–myotendinal junction
What can skeletal muscle be terminated on?
A thin sheet connective tissue call fascia or aponeurosis
What are connective tissue the basis for?
Structural integrity of a muscle
What is skeletal muscle?
Large cells within a vast network of connective tissues
What are the 3 major connective tissues?
Epimysium
Perimysium
Endomysium
What does epimysium do?
Separates muscles
What is epimysium made of?
Nerves
Blood vessels
At least 1 artery, 1 vein, and a bundle of nerves
What does perimysium do?
Separates muscle bundles
How many muscle fibers are in a primary bundle of perimysium?
20 to 40
What do primary bundles of perimysium form?
Secondary bundle
What is within the perimysium?
Intramuscular fat
What does endomysium do?
Separates muscle fibers
What is the endomysium adjacent to?
Muscle cells membrane
What is the endomysium responsible for?
Meat tenderness
Know the summary of physical characteristics on slide 11 and 23
Know the summary of physical characteristics on slide 11 and 23
How do the connective tissues vary?
Greatly in physical and functional characteristics
What are 3 types of connective tissue fibers?
Collagenous
Reticular
Elastic
What is the ground substances of connective tissue?
Proteoglycans: chondroitin sulfates, hyaluronic acid
What is hyaluronic acid?
Fluid at articulations of the skeletal system
What is the most abundant protein in an animal?
Collagen
How much of body protein is collagen?
20-30% of body protein
What is the polypeptide composition of collagen fibers? (5)
α-chain 1014 to 1023 aa residues Unique and repeating sequences 3 α helices Pentafibrils
What is the repeating sequences of polypeptide composition made of?
Proline
Hydroxyproline
glycine
What is the process of collagen formation? (8)
Gene–DNA Hydroxylation Glycosylation Helix formation Procollagen Tropocollagen Crosslinking Collage
What do different types of collagen differ in?
α-chains in triple helical collagen molecules
What are the differences of α-chanis of collagen?
AA composition
What is reticular fibers?
Smaller bundle of fibers with small fibers, high reticulin content, high % ground substance, and delicate connective tissues around organs