Review Muscular System(lecture) Flashcards
Which list of organs contains smooth muscle tissue?
a) blood vessels, stomach, esophagus
b) bladder, uterus, small intestine
c) biceps brachii, triceps brachii (muscles of the arm)
d) heart
e) both blood vessels, stomach, esophagus and bladder, uterus, small intestine
e) both blood vessels, stomach, esophagus and bladder, uterus, small intestine
Which type of muscle tissue is involuntary (can’t be consciously controlled)?
a) skeletal muscle
b) smooth muscle
c) cardiac muscle
d) a and b only
e) b and c only
e) b and c only (Smooth & Cardiac)
Which of the following is not a function of skeletal muscle tissue?
a) moving your eyes from left to right as you read this question
b) holding your head up
c) shivering to generate body heat when you’ve become chilled
d) moving food through the small intestine
e) stabilizing joints and helping to maintain body positions
d) moving food through the small intestine
Skeletal muscle is covered, surrounded and protected by various layers of connective tissue. Which layer of connective tissue would surround a bundle of muscle fibers (muscle cells)?
a) epimysium
b) hypodermis
c) fascia
d) perimysium
e) endomysium
d) perimysium
Muscular tissue has several important properties, such as electrical excitability. Another property of muscular tissue is that it is able to stretch, and return to its original size and shape. Which property of muscular tissue is this?
a) Conductivity
b) Elasticity
c) Extensibility
d) Plasticity
e) None of these are correct
b) Elasticity
In the drawing, the circle is indicating a:
a) somatic motor neuron.
b) filament.
c) myofibril.
d) muscle fiber.
e) myofibril fascicle.
d) muscle fiber.
Which of the following is not a function of the structure indicated in the image?
a) It is similar to the smooth endoplasmic reticulum found in non-muscle cells.
b) When a muscle cell is contracting, it stores calcium ions.
c) It stores calcium ions in enlarged regions called terminal cisterns.
d) This system of tubules surrounds each myofibril in a muscle cell.
b) WHEN A MUSCLE CELL IS CONTRACTING, IT STORES CALCIUM IONS.
The contractile organelle of skeletal muscle fibers is:
a) the endoplasmic reticulum
b) the myofilament
c) the T tubule
d) the myofibril
e) the sarcomere (basic functional unit of a myofibril)
d) the myofibril
The site where a somatic motor neuron releases acetylcholine to stimulate a skeletal muscle fiber is called the:
a) neuromuscular junction
b) synaptic end bulbs
c) motor end plate
d) myofibril
e) sarcolemma
a) neuromuscular junction
Native people of the Amazon basin in South America use curare, a poison, on arrows and blow darts, to paralyze and bring down small game. Which part of the sequence of events at the neuromuscular junction does curare specifically disrupt?
a) release of acetylcholine (ACh)
b) activation of ACh receptors
c) production of a muscle action potential
d) activation of acetylcholinesterase
e) release of calcium from the terminal cisterns
b) activation of ACh receptors
Which of the following molecules found in skeletal muscle cells binds oxygen that can later be used during aerobic metabolism to help generate ATP?
a) creatine
b) creatine phosphate
c) myoglobin
d) titin
e) glycogen
c) myoglobin
Which structure occurs at the border between two adjacent sarcomeres? Consult the image for assistance.
a) thin filament
b) thick filament
c) Z disc
d) M line
e) A band
c) Z disc
At which stage of the contraction cycle (see diagram) do the myosin heads bind ATP, causing the crossbridges to detach from the actin filament?
a) Stage 1
b) Stage 2
c) Stage 3
d) Stage 4
e) That stage is not shown
d) Stage 4
During the contraction cycle, ATP attaches to
a) actin
b) troponin
c) myosin
d) tropomyosin
e) none of these choices
c) myosin
Which of the following is directly responsible for transmitting an action potential from a motor neuron to a skeletal muscle fiber?
a) gap junctions
b) intercalated discs
c) myofibrils
d) creatine phosphate
e) acetylcholine
e) acetylcholine
Why does skeletal muscle require more ATP than many other tissues in the body?
1. both contraction and relaxation require ATP to occur
2.the sarcoplasmic reticulum uses ATP to “pump” calcium ions back into the terminal cisterns after contraction
- ATP is needed to convert creatine into creatine phosphate needed to provide energy at the beginning of muscle contraction
a) 1 only
b) 2 only
c) 3 only
d) 1,2 &3
e) Only 1 and 3
d) 1,2 &3
Which of the following statements about creatine are correct?
a) some studies have shown it boosts athletic performance when taken as a supplement
b) some studies have shown no benefit to athletic performance when it is taken as a supplement
c) it is harmful, and will cause kidney damage
d) all of these choices are correct
e) some studies have shown it boosts athletic performance when taken as a supplement and some studies have shown no benefit to athletic performance when it is taken as a supplement
e) some studies have shown it boosts athletic performance when taken as a supplement and some studies have shown no benefit to athletic performance when it is taken as a supplement
A skeletal muscle fiber can produce ATP in a variety of ways (metabolic pathways), however one method produces enough ATP to support physical activity for many hours. Which statement below is correct about this pathway?
a) This is the pathway that produces lactic acid.
b) This is the pathway that uses creatine phosphate to convert ADP to ATP.
c) This pathway is anaerobic.
d) This pathway is aerobic.
e) This is the pathway that produces lactic acid and is anaerobic.
d) This pathway is aerobic.
Which of the following would not be a contributing factor to muscle fatigue?
a) release of excessive amounts of acetylcholine at the neuromuscular junction
b) a feeling that you want to quit, that the activity is too difficult (central fatigue)
c) depletion of adequate supplies of oxygen and ATP
d) a buildup of lactic acid
e) all of these contribute to muscle fatigue
a) release of excessive amounts of acetylcholine at the neuromuscular junction
Which of the following muscle groups would be more likely to have many small motor units (one motor neuron, and just a few muscle fibers under its control)?
a) the muscles that control eye movement
b) the postural muscles that control standing
c) the muscles that control the many movements of the hands
d) all of these choices would have many small motor units
e) only a and c would have many small motor units
e) ONLY A AND C WOULD HAVE MANY SMALL MOTOR UNITS
To delay the onset of muscle fatigue, not all the motor units in a muscle will contract at the same time. Some will remain relaxed while others are contracting. If the contraction continues, and greater force is needed, more motor units will be recruited. T/F?
a) True
A small amount of muscle tension and muscle definition (the appearance of muscle beneath the skin) is present even in a relaxed muscle. A person who is physically fit due to regular exercise, will have more of this characteristic of muscle tissue than someone who is not fit. What is this characteristic?
a) muscle contraction
b) muscle refraction
c) muscle tone
d) muscle refraction
e) muscle recruitment
c) muscle tone
Which of the following statements is correct about why a person’s muscles get larger after weeks of regular exercise and strength training?
a) the person has been able to change the proportion of skeletal muscle fiber types in the exercised muscles (i.e., they’ve added more slow oxidative fibers to their muscles)
b) the person has stimulated some of their muscle fibers to reproduce—they have added additional cells to their exercised muscles
c) the person has added more thin and thick filaments to their muscles
d) all of these choices can happen with exercise
e) none of these choices explain muscle enlargement
c) the person has added more thin and thick filaments to their muscles
Stretching is most effective at reducing injury and promoting greater flexibility if it is done over the course of many weeks, and always when the muscle is cold (before beginning to exercise). T/F?
b) False
