Ch 5 Flashcards
(25 cards)
Dark A bands of skeletal muscle fibers corresponds to the length of _____ filaments, and these bands _____ during contraction
Myosin
Stay the same width
An Olympic sprinter would likely have a higher proportion of _____ fibers than an Olympic marathon runner
Fast glycolytic
Red skeletal muscle fibers have a relatively _____ twitch speed and primarily use _____ respiration
Slow
Aerobic
Tetanus in a muscle cell is caused by ___ in the sarcoplasm
Accumulation of calcium ions
The sliding filament model of contraction in striated muscle involves ____ during contraction
Myosin pulling actin toward the center of the sarcomere
During skeletal muscle excitation, ____\ is released by motor neurons at the neuromuscular junction
ACh
The asymmetric activation of ____ causes relative movement of _____ pairs in the axoneme during ciliary and flagellar movement
Dynein
Microtubule
A low concentration of calcium ions in the sarcoplasm promotes
The blockage of binding sites on actin
During skeletal muscle relaxation, calcium ions move into the
Sarcoplasmic reticulum
The extension of the cell membrane during amoeboid movement is cause by ____
Actin polymerization
Microfilaments are polymers composed of the protein ____ and they (microfilaments) are
Actin
Part of the cytoskeleton
During the dispersion of pigment granules in a melanocyte, the ___ guides the path of movement and _____ provides the mechanical force for movement
Microtubule
Kinesin
The structure of an axoneme in a ____ consisted of microtubules in a ____ arrangement
Flagellum
Nine plus two
Isoforms of ____ provide the functional properties of different types of striated muscle fibers in mammals
Myosin II
In smooth muscle, _____ binds calcium ions during contraction and ___ blocks binding sites on actin during relaxation
Calmodulin
Caldesmon
In contrast to skeletal muscle, cardiac muscle is ______ and has a _____ refractory period
Myogenic
Long
_____ muscle lacks striations, sarcomeres, and t tubules
Smooth
The walls of the _____ do not have smooth muscle
Heart
The electric organs of fish are composed of modified muscle referred to as _____
Trans-differentiated
In contrast to resistance (strength) training, endurance training tends to increase _____ in skeletal muscle fibers and convert fibers from ______
Myoglobin content
Fast-glycolytic to fast-oxidative
During skeletal muscle contraction, calcium ions move from the _____ into the _____
Sarcoplasmic reticulum
Sarcoplasm
Microtubules are polymers composed of the protein ______ and they (microtubules) are _____
Tubulin
Part of the cytoskeleton
Movement due to microfilaments often uses the motor protein _____
Myosin
An increase in the number of activated motor units for a muscle is referred to as
Recruitment
