BIO 161 PSU EXAM 4 QUESTIONS AND ANSWERS A+ GRADED
What are the three types of muscle tissue?
skeletal, cardiac, smooth
What are some characteristics of skeletal muscle?
-Voluntary
- Striated
- Multinucleate
- Attached to bone or fascia (connective tissue)
What are some characteristics of cardiac muscle?
- Involuntary
- Striated
- Mononucleate
- Autorhythmic (cells can self-regulate contraction)
What are some characteristics of smooth muscle?
- Involuntary
- Non-striated
- Mononucleate
What are the 5 properties of muscle tissue?
excitability, conductivity, contractility, extensibility, elasticity
What is excitability?
respond to chemicals released from motor neurons
What is conductivity?
ability to propagate electrical signals over membrane
What is contractility?
ability to shorten and generate force
What is extensibility?
ability to be stretched without damaging the tissue
What is elasticity?
ability to return to original shape after being stretched
What is formed by a group of fascicles?
Muscle
What is formed by a group of muscle fibers?
Fascicle
What is formed by a group of myofibrils?
Muscle fibers
What do myofibrils contain?
bundles of protein filaments, organized into sarcomeres
What are three functions of connective tissue?
-Protects muscle cells
-Reduces friction
-Creates space for extracellular fluid
What are the three layers of connective tissue?
Epimysium, Perimysium, Endomysium
What is the main characteristic of epimysium connective tissue?
, Covers entire muscle
What is the main characteristic of Perimysium connective tissue?
Covers fascicles
What is the main characteristic of Endomysium connective tissue?
Covers muscle fibers
What is the most common muscle connection?
Muscle to bone/indirect
What is indirect muscle connection?
When collagen fibers of epimysium form strong fibrous tendon (dense regular
connective tissue) that merges into periosteum (outer covering of bone)
What is direct muscle connection?
When collagen fibers of
epimysium are
directly continuous
with periosteum
What is a muscle to fascia connection?
When muscles insert to broad sheet of connective tissue called an aponeurosis: similar
in structure as a tendon, but broad and flat
What is muscle shape baed on?
the organization of fascicles
True or false? Muscles with more muscle cells can generate more force, while
muscles with longer muscle cells can contract further
True
What is the sarcolemma?
muscle cell membrane
What is the sarcoplasm?
cytoplasm of a muscle cell
What is inside the sarcoplasm?
myofibrils, myoglobin, glycogen
What are transverse tubules?
Tube-like structures which penetrate the interior of the cell located in the sarcolemma
What is sarcoplasmic reticulum?
muscle cell ER
What are myofibrils?
bundles of three types of proteins
What are the three types of proteins found in myofibrils?
-Thick filaments (myosin)
-Thin filaments (actin, troponin, tropomyosin)
-Elastic filaments (titin)
What are filaments responsible for?
muscle contraction
Filaments are organized into functional units called?
sarcomeres
Thick filaments consist of?
a polymer of myosin proteins
True or false? One thick filament consists of hundreds of myosin proteins
What are the three types of muscle tissue?
skeletal, cardiac, smooth
What are some characteristics of skeletal muscle?
-Voluntary
- Striated
- Multinucleate
- Attached to bone or fascia (connective tissue)
What are some characteristics of cardiac muscle?
- Involuntary
- Striated
- Mononucleate
- Autorhythmic (cells can self-regulate contraction)
What are some characteristics of smooth muscle?
- Involuntary
- Non-striated
- Mononucleate
What are the 5 properties of muscle tissue?
excitability, conductivity, contractility, extensibility, elasticity
What is excitability?
respond to chemicals released from motor neurons
What is conductivity?
ability to propagate electrical signals over membrane
What is contractility?
ability to shorten and generate force
What is extensibility?
ability to be stretched without damaging the tissue
What is elasticity?
ability to return to original shape after being stretched
What is formed by a group of fascicles?
Muscle
What is formed by a group of muscle fibers?
Fascicle
What is formed by a group of myofibrils?
Muscle fibers
What do myofibrils contain?
bundles of protein filaments, organized into sarcomeres
What are three functions of connective tissue?
-Protects muscle cells
-Reduces friction
-Creates space for extracellular fluid
What are the three layers of connective tissue?
Epimysium, Perimysium, Endomysium
What is the main characteristic of epimysium connective tissue?
, Covers entire muscle
What is the main characteristic of Perimysium connective tissue?
Covers fascicles
What is the main characteristic of Endomysium connective tissue?
Covers muscle fibers
What is the most common muscle connection?
Muscle to bone/indirect
What is indirect muscle connection?
When collagen fibers of epimysium form strong fibrous tendon (dense regular
connective tissue) that merges into periosteum (outer covering of bone)
What is direct muscle connection?
When collagen fibers of
epimysium are
directly continuous
with periosteum
What is a muscle to fascia connection?
When muscles insert to broad sheet of connective tissue called an aponeurosis: similar
in structure as a tendon, but broad and flat
What is muscle shape baed on?
the organization of fascicles
True or false? Muscles with more muscle cells can generate more force, while
muscles with longer muscle cells can contract further
True
What is the sarcolemma?
muscle cell membrane
What is the sarcoplasm?
cytoplasm of a muscle cell
What is inside the sarcoplasm?
myofibrils, myoglobin, glycogen
What are transverse tubules?
Tube-like structures which penetrate the interior of the cell located in the sarcolemma
What is sarcoplasmic reticulum?
muscle cell ER
What are myofibrils?
bundles of three types of proteins
What are the three types of proteins found in myofibrils?
-Thick filaments (myosin)
-Thin filaments (actin, troponin, tropomyosin)
-Elastic filaments (titin)
What are filaments responsible for?
muscle contraction
Filaments are organized into functional units called?
sarcomeres
Thick filaments consist of?
a polymer of myosin proteins
True or false? One thick filament consists of hundreds of myosin proteins
