Chapter 1 & 11 Flashcards
The Anatomy of skeletal muscle consist of what 2 things?
Muscle fibers
Myofibrils
What are the 3 types of muscle tissue?
Skeletal
Smooth
Cardiac
Of the 3 types of muscle tissue, which is voluntary?
Skeletal
What does the skeletal muscle connect to?
Skeleton
Where is smooth muscle found?
Hollow organs
Where is cardiac muscle found?
Heart
An entire muscle is surrounded by __________.
Epimysium
An entire muscle consists of many _______ (fascicles or fasciculi)
Bundles
The fascicle is surrounded by _______.
Perimysium
The fascicle consist of individual _____ cells.
Muscle
Each muscle fiber is surrounded by _________.
Endomysium
Muscle fivers consists of myofibrils divided into _________.
Sacromeres
Plasmalemma (cell membrane) fuses with _____.
Tendon
What are the 3 jobs of plasmalemma? (CapMpTn)
- conducts action potential
- maintains pH
- Transports nutrients
What is the cytoplasm of the muscle cell?
Sarcoplasm
What are 2 unique features of sarcoplasm? (GsM)
Glycogen storage & myoglobin
_________ are extensions of plasmalemma.
Transverse tubules
What carries action potential deep into muscle fiber?
T-Tubules
Where is Calcium stored in muscle fibers?
Sarcoplasmic reticulum
What is the sequence of myofibril creation?
Muscle —> fascicle —> muscle fiber —> myofibril
What is the amount of myofibrils per muscle fiber?
Hundreds to thousands
Sections of myofibrils are known as what?
Sarcomeres
What is the basic contractile element of skeletal muscle?
Sarcomeres
To estimate the full length of a myofibril, how should you measure it?
End to end
What are the distinctive striped appearances located on sarcomeres?
Striations
Describe Sarcomere A-bands.
Dark/blue stripes
Describe Sarcomere I-bands.
light/pink stripes
Describe Sarcomere H-zone.
Middle of A-band
Describe Sarcomere M-line.
middle of H-zone
T/F: A-band has both thick and thin filament
True
T/F: A-bands length is measured using both thick and thin filament.
False; only thick filament
T/F: I-band consists of thin filament.
True
What is common boundary structure of the sarcomere?
Z-disk or Z-line
T/F: H-zone consists of thick filament.
True
What are 2 important proteins of the sarcomere?
Actin & Myosin
Thin filaments are composed of what 3 proteins?
Actin
Tropomyosin
Troponin
_______: contains myosin-binding site.
Actin
What protein covers the active site at rest?
Tropomyosin
What protein is anchored to actin and moves Tropomyosin?
Troponin
Myosin is two intertwined ________ with globular heads.
Filaments
T/F: Globular heads can protrude 360 degrees from thick filament axis.
True
T/F: Globular heads will not interact with actin filaments for contraction.
False; they will interact
T/F: Myosin uses Titin as a stabilizer.
True
What myofilament acts like a spring?
Titin
T/F: Titin extends from Z-disk to M-band.
True