10-11 Flashcards
What is one of the four primary tissue types in the body responsible for movement and contraction?
A) Epithelial tissue
B) Muscle tissue
C) Nervous tissue
D) Connective tissue
Answer: B) Muscle tissue
Approximately what percentage of an individual’s body weight is muscle tissue?
A) 25%
B) 50%
C) 75%
D) 90%
Answer: B) 50%
Which characteristic of muscle allows it to respond to stimuli?
A) Contractibility
B) Excitability
C) Extensibility
D) Elasticity
Answer: B) Excitability
What type of muscle tissue is found attached to bones?
A) Cardiac muscle
B) Smooth muscle
C) Skeletal muscle
D) Epithelial muscle
Answer: C) Skeletal muscle
Which type of muscle is involuntary and found only in the heart?
A) Skeletal muscle
B) Cardiac muscle
C) Smooth muscle
D) All muscle types
Answer: B) Cardiac muscle
Smooth muscle cells are typically shaped like what?
A) Cylinders
B) Branches
C) Spindles
D) Striations
Answer: C) Spindles
Which type of muscle has striations and intercalated discs?
A) Skeletal muscle
B) Smooth muscle
C) Cardiac muscle
D) All muscle types
Answer: C) Cardiac muscle
What is the primary function of skeletal muscles?
A) Pumping blood
B) Movement of the skeleton
C) Maintaining organ shape
D) Digesting food
Answer: B) Movement of the skeleton
What type of connective tissue surrounds the entire muscle?
A) Endomysium
B) Perimysium
C) Epimysium
D) Aponeurosis
Answer: C) Epimysium
Which structure in muscle fibers is responsible for calcium storage?
A) Sarcolemma
B) Sarcoplasmic reticulum
C) Myofibril
D) Myofilament
Answer: B) Sarcoplasmic reticulum
What is the area called where a motor neuron innervates a muscle cell?
A) Neuromuscular junction
B) Sarcomere
C) Synaptic cleft
D) Axon terminal
Answer: A) Neuromuscular junction
During muscle contraction, what binds to troponin to initiate the contraction process?
A) Sodium ions
B) Acetylcholine
C) Calcium ions
D) Potassium ions
Answer: C) Calcium ions
What mechanism describes how muscle fibers contract?
A) Cross-bridge cycling
B) Isometric contraction
C) Hyperpolarization
D) Anaerobic respiration
Answer: A) Cross-bridge cycling
What happens during the power stroke of muscle contraction?
A) Calcium binds to troponin
B) Myosin heads pivot
C) ATP is produced
D) Actin moves away
Answer: B) Myosin heads pivot
Which energy source is primarily used for immediate muscle contraction?
A) Glucose
B) ATP
C) Glycogen
D) Creatine phosphate
Answer: B) ATP
Which type of muscle contraction occurs when muscle length changes to move a load?
A) Isometric contraction
B) Isotonic contraction
C) Static contraction
D) Dynamic contraction
Answer: B) Isotonic contraction
What is the term for the amount of oxygen needed to restore ATP levels after exercise?
A) Oxygen debt
B) Muscle fatigue
C) Aerobic threshold
D) Metabolic demand
Answer: A) Oxygen debt
Which type of skeletal muscle fiber has high resistance to fatigue?
A) Fast-glycolytic
B) Slow-oxidative
C) Fast-oxidative
D) All muscle fibers
Answer: B) Slow-oxidative
What occurs when multiple motor units are activated to increase muscle strength?
A) Muscle tension
B) Recruitment
C) Summation
D) Twitch
Answer: B) Recruitment
What is the primary structural unit of skeletal muscle?
A) Fiber
B) Sarcomere
C) Myofibril
D) Myofilament
Answer: B) Sarcomere
Which type of contraction does not change muscle length?
A) Isotonic
B) Isometric
C) Eccentric
D) Concentric
Answer: B) Isometric
What is a single stimulus-contraction-relaxation sequence in a muscle fiber called?
A) Myogram
B) Wave summation
C) Twitch
D) Tetanus
Answer: C) Twitch
What can cause muscle fatigue?
A) High levels of ATP
B) Excessive lactic acid
C) Abundant oxygen
D) Increased muscle tone
Answer: B) Excessive lactic acid
Which muscle type is typically involved in endurance exercise?
A) Fast-glycolytic fibers
B) Slow-oxidative fibers
C) Fast-oxidative fibers
D) All muscle types
Answer: B) Slow-oxidative fibers
Which substance is often associated with muscle hypertrophy?
A) Lactic acid
B) Creatine phosphate
C) Anabolic steroids
D) ATP
Answer: C) Anabolic steroids
What is the primary function of cardiac muscle?
A) Voluntary movement
B) Pumping blood
C) Digestion
D) Body support
Answer: B) Pumping blood
Which characteristic is unique to cardiac muscle?
A) Multi-nucleated
B) Short and branched cells
C) Striations only
D) Voluntary control
Answer: B) Short and branched cells
Which muscle type is found in the walls of hollow organs?
A) Skeletal muscle
B) Cardiac muscle
C) Smooth muscle
D) Epithelial muscle
Answer: C) Smooth muscle
What type of muscle fiber is predominantly used during high-intensity exercise?
A) Slow-oxidative
B) Fast-glycolytic
C) Fast-oxidative
D) Cardiac muscle
Answer: B) Fast-glycolytic
What do intercalated discs in cardiac muscle tissue contain?
A) Myofibrils
B) Gap junctions and desmosomes
C) Sarcoplasmic reticulum
D) Actin and myosin
Answer: B) Gap junctions and desmosomes
Which process occurs when muscle fibers are stimulated at a high frequency?
A) Tetanus
B) Fatigue
C) Wave summation
D) Recruitment
Answer: A) Tetanus
What initiates the contraction process in muscle fibers?
A) ATP binding
B) Calcium release
C) Sodium influx
D) Motor neuron stimulation
Answer: B) Calcium release
What does the term ‘hypertrophy’ refer to?
A) Muscle wasting
B) Muscle increase in size
C) Muscle contraction
D) Muscle relaxation
Answer: B) Muscle increase in size
Which type of muscle fibers have a high myoglobin content?
A) Slow-oxidative
B) Fast-glycolytic
C) Fast-oxidative
D) All muscle types
Answer: A) Slow-oxidative
What structure allows for the electrical signal to spread throughout muscle fibers?
A) T-tubules
B) Sarcoplasm
C) Epimysium
D) Neuromuscular junction
Answer: A) T-tubules
What happens to the muscle when the load exceeds the muscle’s tension during an isometric contraction?
A) Muscle shortens
B) Muscle relaxes
C) Muscle length remains the same
D) Muscle hypertrophies
Answer: C) Muscle length remains the same
What happens to muscle fibers when they are exposed to regular resistance training?
A) Atrophy
B) Hypertrophy
C) Necrosis
D) Fibrosis
Answer: B) Hypertrophy
What is the term for the period when a muscle is stimulated but has not yet begun to contract?
A) Contraction phase
B) Relaxation phase
C) Latent period
D) Recovery phase
Answer: C) Latent period
Which ion is crucial for muscle contraction to occur?
A) Sodium
B) Potassium
C) Calcium
D) Chloride
Answer: C) Calcium
What is the role of the sarcoplasmic reticulum in muscle fibers?
A) ATP production
B) Storage and release of calcium
C) Providing energy for contraction
D) Forming muscle fiber structure
Answer: B) Storage and release of calcium
What does the term ‘muscle tone’ refer to?
A) Complete muscle relaxation
B) The state of partial contraction of muscles
C) Muscle hypertrophy
D) Muscle atrophy
Answer: B) The state of partial contraction of muscles
What type of muscle fibers are best suited for sprinting?
A) Slow-oxidative fibers
B) Fast-glycolytic fibers
C) Fast-oxidative fibers
D) Cardiac muscle fibers
Answer: B) Fast-glycolytic fibers
What adaptation occurs in muscles as a response to aerobic training?
A) Increased myofibril size
B) Increased mitochondrial density
C) Decreased capillary networks
D) Decreased endurance
Answer: B) Increased mitochondrial density
Which structure helps to anchor the thick filaments in a sarcomere?
A) Z-line
B) M-line
C) A-band
D) I-band
Answer: B) M-line
What is the primary neurotransmitter released at the neuromuscular junction?
A) Norepinephrine
B) Dopamine
C) Acetylcholine
D) Serotonin
Answer: C) Acetylcholine
Which type of muscle fiber is characterized by high fatigue resistance?
A) Fast-twitch fibers
B) Slow-twitch fibers
C) Intermediate fibers
D) None of the above
Answer: B) Slow-twitch fibers
What occurs during the recovery phase after intense exercise?
A) Decreased oxygen consumption
B) Oxygen debt is repaid
C) Increased heart rate
D) All of the above
Answer: B) Oxygen debt is repaid
Which muscle type has a higher density of mitochondria?
A) Skeletal muscle
B) Cardiac muscle
C) Smooth muscle
D) Both skeletal and cardiac muscle
Answer: D) Both skeletal and cardiac muscle
What is the function of the intercalated discs in cardiac muscle?
A) Increase contraction speed
B) Provide mechanical and electrical connections
C) Store calcium ions
D) Prevent fatigue
Answer: B) Provide mechanical and electrical connections
What is the main energy source for muscle contraction during short, intense activities?
A) Fatty acids
B) Glycogen
C) Creatine phosphate
D) Glucose
Answer: C) Creatine phosphate
