BIO 201 EXAM 3 EXAMPREP STUDY GUIDE
QUESTIONS AND CORRECT ANSWERS
COMPLETE REVIEW MATERIAL
●● List AND describe the characteristics of skeletal muscle
Answer: Responsiveness:(excitability)
to chemical signals, stretch and electrical changes across the plasma
membrane
Conductivity:
local electrical change triggers a wave of excitation that travels along the
muscle fiber
Contractility: shortens when stimulated
Extensibility: capable of being stretched
Elasticity: returns to its original resting length after being stretched
●● What are two other names for a muscle fiber?
Answer: Myofiber, myocyte
●● Describe the number and location of nuclei in a myofiber
Answer: Many nuclei under the sarcolemma
●● Muscle cells are packed full of which type of protein filament?
, Answer: Actin and myosin
●● Make sure you understand the difference between a myofiber and a
myofibril
Answer: Myofiber=single muscle cell
Myofibril=bundles of actin and myosin
●● What is another name for the muscle cytoplasm?
Answer: Sarcoplasm
●● What is another name for the plasma membrane of a myofiber?
Answer: Sarcolemma
●● Describe the location of the T tubules, sarcoplasmic reticulum, and
terminal cisternae. What is the function of each of these structures?
Answer: T tubules: circle around myofibrils, tunnel like infolding that
penetrate the cell
Sarcoplasmic Reticulum: network around each myofibril
Terminal Cisternae: dilated end tracts which store calcium
●● What is a "triad" referring to?
Answer: 1 t-tubule and 2 terminal cisternea
QUESTIONS AND CORRECT ANSWERS
COMPLETE REVIEW MATERIAL
●● List AND describe the characteristics of skeletal muscle
Answer: Responsiveness:(excitability)
to chemical signals, stretch and electrical changes across the plasma
membrane
Conductivity:
local electrical change triggers a wave of excitation that travels along the
muscle fiber
Contractility: shortens when stimulated
Extensibility: capable of being stretched
Elasticity: returns to its original resting length after being stretched
●● What are two other names for a muscle fiber?
Answer: Myofiber, myocyte
●● Describe the number and location of nuclei in a myofiber
Answer: Many nuclei under the sarcolemma
●● Muscle cells are packed full of which type of protein filament?
, Answer: Actin and myosin
●● Make sure you understand the difference between a myofiber and a
myofibril
Answer: Myofiber=single muscle cell
Myofibril=bundles of actin and myosin
●● What is another name for the muscle cytoplasm?
Answer: Sarcoplasm
●● What is another name for the plasma membrane of a myofiber?
Answer: Sarcolemma
●● Describe the location of the T tubules, sarcoplasmic reticulum, and
terminal cisternae. What is the function of each of these structures?
Answer: T tubules: circle around myofibrils, tunnel like infolding that
penetrate the cell
Sarcoplasmic Reticulum: network around each myofibril
Terminal Cisternae: dilated end tracts which store calcium
●● What is a "triad" referring to?
Answer: 1 t-tubule and 2 terminal cisternea
