MuscularSkeletal system Week 9 Flashcards
1) Muscles exhibit the property of excitability. This means that the muscle
A) shortens its length.
B) recoils to its original resting length.
C) stretches beyond its normal length.
D) responds to stimulation by the nervous system.
E) excites itself.
- D
2) The capacity of a muscle cell to shorten forcefully is known as
A) contractility. B) excitability. C) extensibility. D) elasticity. E) flexibility.
- A
3) Identify the statement concerning general functional characteristics of muscle that is true.
A) Muscle tissue shortens forcefully but lengthens passively.
B) Muscle tissue shortens passively but lengthens forcefully.
C) Muscle tissue can get shorter, but can not get longer.
D) Muscle tissue can get longer, but can not get shorter.
E) None of the above statements are true.
- A
4) Identify the statement concerning skeletal muscle that is true.
A) It comprises about 20% of the body’s weight.
B) It propels urine through the urinary tract.
C) Its function is largely under involuntary control.
D) It is a kind of connective tissue.
E) It is responsible for locomotion.
- D
5) Which of the following actions is caused by contraction of skeletal muscle?
A) contraction of the heart B) moving your feet in walking C) movement of food through the G.I. tract D) emptying of the urinary bladder E) vasoconstriction
- B
6) Smooth muscle and cardiac muscle are similar in that they both
A) are under involuntary control. B) are striated. C) are widely distributed in the body. D) have multiple nuclei. E) are under voluntary control.
- A
7) Which of the following is true?
A) Skeletal muscle is capable of spontaneous contraction.
B) Smooth muscle is found in the walls of hollow organs.
C) Cardiac muscle cells have multiple nuclei.
D) Smooth muscle cells are long and cylindrical.
E) There is a small amount of smooth muscle in the heart.
- B
8) Hypertrophy of skeletal muscles from weight lifting is caused by an increase in the
A) number of muscle fibres. B) size of muscle fibres. C) number of striations. D) number of nuclei within the muscle fibres. E) number of muscle cells.
- B
9) Skeletal muscle fibres
A) possess striations.
B) can contract but are not extensible or excitable.
C) do not require nerve innervation to contract.
D) increase dramatically in number after birth.
E) are found in the walls of the stomach.
- A
10) A fascicle (or fasciculus)
A) is a bundle of reticular fibers. B) is surrounded by perimysium. C) is only found in smooth muscle. D) possesses an external lamina. E) is a bundle of collagen fibers.
- B
11) Endomysium is a delicate network of loose connective tissue that
A) surrounds each muscle fibre. B) forms a sheath around a fasciculus. C) is composed of elastic fibers. D) separates individual muscles. E) penetrates muscle fibers.
- A
12) Which of the following connective tissue layers is outside all the others? A) perimysium B) endomysium C) epimysium D) paramysium E) sarcolemma
- C
13) List the following structures in order from smallest to largest.
- muscle fibre
- myofilament
- myofibril
- muscle fasciculus
A) 4, 2, 3, 1 B) 2, 1, 4, 3 C) 3, 1, 4, 2 D) 2, 3, 1, 4 E) 1, 2, 3, 4
- D
14) Muscle myofibrils
A) are found in the sarcolemma.
B) extend from the sarcolemma to the T-tubule.
C) contain myosin and actin myofilaments.
D) hold muscle cells together.
E) do not appear striated.
- C
15) T tubules
A) provide nutrients to the muscle fiber.
B) generate new muscle fibers.
C) conduct action potentials deep into the muscle cell.
D) release acetylcholine.
E) store calcium ions.
- C
16) The sarcoplasmic reticulum
A) stores calcium ions. B) shortens during muscle contraction. C) transmits nerve impulses to the myofibrils. D) connects adjacent sarcomeres. E) covers the muscle fiber.
- A
17) The sites where a chemical substance is transmitted from the presynaptic terminal of an axon to the postsynaptic membrane of a muscle fiber are called
A) neuromuscular junctions. B) sarcomeres. C) myofilaments. D) Z disks. E) cell body of neuron.
- A
18) Electric signals called action potentials
A) cause a muscle cell to contract.
B) transfer information from cell to cell.
C) make complex mental processes possible.
D) send information to the brain.
E) all of the above
- E
19) Which of the following correctly describes myoglobin’s special function in muscle tissue?
A) breaks down glycogen B) synthesizes ATP C) acts as a reservoir for oxygen D) produces action potentials E) stores glucose.
- C
20) Body temperature
A) is raised by sweating.
B) results from the heat produced when muscles contract.
C) will increase after blood vessels in the skin constrict.
D) is lowered by shivering.
E) decreases when the rate of the chemical reactions increase.
- B
21) Shivering
A) increases heat loss from the skin.
B) is a response of the nervous system to a high fever.
C) helps raise body temperature.
D) causes vasoconstriction.
E) occurs when body temperature is slightly elevated.
- C
22) When comparing smooth and skeletal muscle cells, which of the following statements is true?
A) Smooth muscle cells have striations.
B) The myofilaments in smooth muscle do not form sarcomeres.
C) Smooth muscle cells are larger than skeletal muscle cells.
D) Smooth muscle has a lot of actin and myosin.
E) Smooth muscle cells are multinucleated.
- B
23) Cardiac muscle
A) is found in the walls of blood vessels and in the heart.
B) is largely under voluntary control.
C) is striated.
D) contraction is dependent on stimulation by the nervous system.
E) is unaffected by hormones.
- C
24) Smooth muscle
A) is largely under voluntary control.
B) is located in the coverings of solid organs.
C) is striated.
D) moves blood through the heart
E) is regulated by the autonomic division of the nervous system.
- E
25) Which of the following is a function of muscle tissue?
A) absorbing heat from the environment B) storage of triglycerides C) controlling flow of materials out of the stomach and urinary bladder D) destabilizing body position E) storing calcium
- C
26) The ability to respond to stimuli by producing action potentials
A) is called electrical excitability. B) is a property of muscle tissue. C) is not exhibited by nervous tissue. D) A and B are correct. E) A, B and C are correct.
- D
27) The ability of a muscle tissue to stretch without being damaged is called
A) electrical excitability. B) contractility. C) extensibility. D) irritability. E) elasticity.
- C
28) A muscle fibre (myofibre) is a muscle
A) contractile unit. B) cell. C) protein. D) sarcomere. E) A and B are correct.
- B
29) The outermost extension of deep connective tissue that surrounds a muscle is the
A) endomysium. B) epimysium. C) perimysium D) tendon. E) aponeurosis.
- B
30) A tendon
A) attaches a muscle to a bone.
B) is an extension of the fused endomysium, perimysium and epimysium of a muscle.
C) contains parallel bundles of collagen fibers.
D) A and B are correct.
E) A, B and C are correct.
- E
31) A skeletal myofibre
A) has one centrally located nucleus.
B) is derived from embryonic cells called myoblasts.
C) retains mitotic potential even in the adult.
D) A and B are correct.
E) A, B and C are correct.
- B
32) The sarcoplasm
A) is the extracellular fluid around a myofiber. B) is enriched with glycogen. C) contains hemoglobin to store O2. D) contains few mitochondria. E) includes many nuclei.
- B
33) The sarcoplasmic reticulum of muscle tissue
A) stores Ca2+ ions required for muscle contraction.
B) is called rough endoplasmic reticulum in other tissues.
C) is part of the transverse tubule.
D) is a thread of protein running the length of the muscle cell.
E) removes Ca2+ from the sarcoplasm so that an action potential can be generated.
- A
34) A neuromuscular junction (NMJ)
A) is the synapse of a motor neuron with a muscle fibre.
B) includes the synaptic end bulbs of the muscle fibre.
C) includes the motor endplates of the motor neuron.
D) uses Na+ as a neurotransmitter.
E) All of the above are correct.
- A
35) Each of the following is true EXCEPT that:
A) a single muscle fibre is controlled by through a single neuromuscular junction.
B) a single motor neuron controls a single muscle fibre.
C) the strength of a muscle contraction depends on the number of motor units stimulated.
D) the strength of a muscle contraction depends on the size of the motor units stimulated.
E) a motor unit consists of a somatic motor neuron and the skeletal muscle fibres it controls.
- B
36) Cardiac muscle tissue
A) is autorhythmic.
B) contains branched cells that are connected by intercalated discs.
C) obtains Ca2+ required for contraction from the sarcoplasmic reticulum and the interstitial fluid.
D) maintains contractions for longer periods of time than skeletal muscle tissue.
E) All of the above are correct.
- E
37) A single motor neuron and all of the fibres it innervates is a ____________________.
Answer: motor unit
- motor unit
38) Both skeletal and __________ muscle are striated, but only skeletal muscle is voluntarily controlled.
- cardiac
39) Functions of muscle include moving the body, thermogenesis, storage and movement of materials within the body and ________________________________________
39.stabilizing body position
40) ________________ is a protein found in the sarcoplasm of skeletal muscle cells that binds and releases O2.
- Myoglobin
41) Muscular _____ is a wasting away of muscles that may arise from disuse or denervation.
- atrophy
42) A _______________ is the functional unit of muscle contraction.
- sarcomere
43) ________________ consist of motor neurons and the muscle fibers that they control.
- Motor units
44) Important functions of the skeletal system include
A) protection of the brain and soft organs. B) storage of water. C) production of Vitamin E. D) regulation of acid-base balance. E) integration of other systems.
- A
45) A band of connective tissue that attaches a muscle to a bone is a(n)
A) aponeurosis. B) ligament. C) bursa. D) epimysium. E) tendon.
- E
46) Ligaments attach
A) muscle to muscle. B) bone to bone. C) muscle to bone. D) nerve to bone. E) nerve to muscle.
- B
47) Chondroblasts produce
A) ligaments. B) cartilage matrix. C) bone tissue. D) blood cells. E) synovial fluid.
- B
48) The type of cartilage associated with bone function and development is
A) elastic cartilage. B) fibrocartilage. C) hyaline cartilage. D) interstitial cartilage. E) osteocartilage.
- C
49) Which of the following is correctly matched?
A) short bone - carpal bone B) long bone - vertebra C) irregular bone - femur D) flat bone - phalanges of the toes E) short bone - humerus
- A
50) An example of a long bone would be
A) the sternum. B) a rib. C) a carpal bone. D) the tibia. E) the clavicle.
- D
51)
An X-ray determines that Peter fractured the shaft of his humerus. The break is in the _____________ of the bone.
A) epiphysis B) epiphyseal line C) diaphysis D) growth plate E) articular surface
- C
52) Which of the following membranes covers the surface of a mature bone?
A) perimysium B) perichondrium C) peritendineum D) peritoneum E) periosteum
- E
53) The cell type that is responsible for maintaining bone once it has been formed is the
A) osteoclast. B) osteoblast. C) chondrocyte. D) osteocyte. E) chondroblast.
- D
54) Which of the following cell types is responsible for breaking down bone matrix?
A) chondroclast B) osteoclast C) chondroblast D) fibroblast E) osteocyte
- B
55) The primary function of osteoblasts is to
A) prevent osteocytes from forming. B) resorb bone along the epiphyseal plate. C) inhibit the growth of bone. D) stimulate bone growth. E) lay down bone matrix.
- E
56) Which of the following is correctly matched?
A) osteocytes - function in bone remodeling
B) osteoclasts – responsible for resorption
C) osteoblasts - break down bone tissue
D) endosteum - lines central canal of the osteon
E) periosteum – lines the medullary cavity
- B
57) Cancellous bone tissue
A) is very dense.
B) contains concentric lamellae.
C) contains interconnecting plates called trabeculae.
D) has many spaces and lacks osteocytes.
E) is the primary component of compact bone.
- C
58) Haversian systems or osteons
A) are found in spongy bone tissue. B) lack concentric lamellae. C) are the basic units in compact bone tissue. D) do not contain osteocytes. E) are avascular.
- C
59) The type of lamellae found in osteons (Haversian systems) is
A) circumferential. B) concentric. C) interstitial. D) appositional. E) oppositional.
- B
60) Lamellar bone
A) has its collagen fibers randomly oriented.
B) has a porous appearance.
C) is organized into thin sheets of tissue.
D) is very light in weight.
E) is not easily restructured.
- C
61) You would look for concentric lamellae
A) around the central canal of an osteon.
B) in between osteons.
C) on the outer surface of compact bone tissues.
D) as components of the cartilage.
E) in the bone marrow.
- A
62) Long bones grow in length at the
A) epiphyseal plate. B) articular cartilage. C) center of the shaft. D) endosteum-periosteum junction. E) in the center of the epiphysis.
- A
63) The longitudinal growth of long bones ceases when
A) chondroblasts take over mitosis of osteoblasts.
B) the epiphyseal plate is completely replaced with bone tissue.
C) the epiphysis becomes separated from the diaphysis.
D) the bone marrow forms.
E) the periosteum is completed.
- B
64) Which of the following statements about bone remodeling and repair is correct?
A) Bone remodeling involves removal of old bone by osteoblasts.
B) As a long bone increases in diameter, the size of the marrow cavity decreases.
C) The rate of bone remodeling increases in the elderly.
D) Exposure of a bone to increased stress can lead to bone remodeling.
E) Bone remodeling does not involve the activity of the osteoclasts and the osteoblasts.
- D
65) The remodeling of bone tissue is a function of
A) osteoblast and osteoclast activity. B) osteoclast and osteocyte activity. C) chondroblast and osteoclast activity. D) chondrocyte and osteocyte activity. E) fibroblast and chondroblast.
- A
66) Bone remodeling may occur
A) as bones grow. B) as bones adjust to stress. C) as fractures heal. D) constantly during a person’s lifetime. E) all of the above
- E
67) Which of the following statements regarding calcium homeostasis is true?
A) Parathyroid hormone inhibits osteoclast activity.
B) When blood calcium levels are too low, osteoclast activity increases.
C) Increased osteoblast activity increases blood calcium levels.
D) Parathyroid hormone increases calcium loss from the kidney.
E) Calcitonin elevates blood calcium levels.
- B
73) The humerus is an example of a _____ bone.
A) long B) short C) flat D) irregular E) sesamoid
- A
74) The ankle bones are examples of _____ bones.
A) long B) short C) flat D) irregular E) sesamoid
- B
75) The sternum is an example of a _____ bone.
A) long B) short C) flat D) irregular E) sesamoid
- C
76) The vertebrae are examples of _____ bones.
A) long B) short C) flat D) irregular E) sesamoid
- D
77) Mature bone cells are called
A) osteocytes. B) osteoblasts. C) osteoclasts. D) chondrocytes. E) osteons.
- A
78) Cells that synthesize the organic components of the bone matrix are called
A) osteocytes. B) osteoprogenitor cells. C) osteoblasts. D) osteoclasts. E) chondrocytes.
- C
79) Large, multinucleated cells that can dissolve the bony matrix are called
A) osteocytes. B) osteoprogenitor cells. C) osteoblasts. D) osteoclasts. E) chondrocytes.
- D
80) In the process of osteolysis,
A) new bone is formed.
B) an organic framework is formed.
C) the bony matrix is dissolved to release the stored minerals.
D) osteoblasts form the osteoid that is later calcified.
E) fractured bones repair themselves.
- C
81) Bone contains all of the following, except
A) calcium phosphate. B) collagen fibers. C) calcium carbonate. D) chondroitin sulfate. E) hydroxyapatite.
- D
82) The narrow passageways that contain cytoplasmic extensions of osteocytes are called
A) lamellae. B) lacunae. C) canaliculi. D) marrow cavities. E) matrices.
- C
83) The central canal of an osteon contains
A) bone marrow. B) osteocytes. C) concentric lamellae. D) blood vessels. E) lacunae.
- D
84) The tiny plates of bone material found in spongy bone are called
A) osteons. B) trabeculae. C) concentric lamellae. D) interstitial lamellae. E) lacunae.
- B
85) The type of bone that is adapted to withstand stresses that arrive from a limited range of directions is _____ bone.
A) spongy B) trabecular C) compact D) lamellar E) irregular
- C
86) The medullary cavity of bones contains
A) compact bone. B) osteons. C) cartilage. D) marrow. E) periosteum.
- D
87) The shaft of a long bone is called the
A) epiphysis. B) diaphysis. C) epiphyseal plate. D) metaphysis. E) lamella.
- B
88) The lining of the marrow cavity is called the
A) endosteum. B) periosteum. C) epimysium. D) perimysium. E) perichondrium.
- A
89) Calcification refers to the
A) formation of new bone tissue.
B) deposition of calcium salts within a tissue.
C) deposition of calcium salts within a bone.
D) release of calcium from bone.
E) repair of fractured bones.
- B
90) Excess growth hormone prior to puberty would result in
A) osteoporosis. B) osteopenia. C) rickets. D) giantism. E) dwarfism.
- D
91) A lack of exercise would
A) cause bones to become thicker. B) cause bones to store more calcium. C) result in thin and brittle bones. D) increase the length of a bone. E) have no effect on a bone.
- C
92) When stress is applied to a bone,
A) the minerals in the bone produce a weak electrical field that attracts osteoblasts.
B) osteoclast activity increases.
C) the bone becomes thin and brittle.
D) the bone compensates by becoming thinner in the region of stress.
E) trabeculae are formed perpendicular to the zone of stress to increase strength.
- A
93) A condition that produces a reduction in bone mass sufficient to compromise normal function is
A) osteopenia. B) osteoporosis. C) osteomyelitis. D) osteitis. E) osteomalacia.
- B
95) _____ fractures are completely internal; they do not break through the skin.
A) Open B) Closed C) Compound D) Recurrent E) both B and D
- B
96) Bones that develop within tendons are called _____ bones.
A) irregular B) sesamoid C) sutural D) Wormian E) tendon
- B
97) Small, flat, oddly shaped bones found between some of the large flat bones of the skull are called _____ bones.
A) irregular B) sesamoid C) sutural D) sagittal E) tendon
- C
98) The basic functional units of mature compact bone are called
A) lacunae. B) osteocytes. C) osteons. D) canaliculi. E) lamellae.
- C
99) The deposition of calcium salts in tissues other than bone is referred to as
A) endochondral ossification. B) intramembranous ossification. C) calcification. D) osteogenesis. E) remodeling.
- C
100) _____ bones develop inside tendons and are most commonly located near joints at the knees, the hands, and the feet.
A) Irregular B) Sesamoid C) Short D) Long E) Flat
- B
101) The patella is an example of a _____ bone.
A) long B) short C) flat D) irregular E) sesamoid
- E
102) In relationship to the diaphysis of a long bone, the osteons are
A) distal. B) anterior. C) parallel. D) proximal. E) posterior.
- C
103) _____ marrow is found between the trabeculae of spongy bone.
A) Bone B) Yellow C) White D) Gray E) Red
- E
104) The lacunae of bone contain
A) blood cells. B) osteocytes. C) chondroblasts. D) bone marrow. E) osteons.
- B
105) How would increasing the proportion of organic molecules to inorganic components in the bony matrix affect the physical characteristics of bone?
A) The bone would be less flexible. B) The bones would be stronger. C) The bones would be more brittle. D) The bones would be more flexible. E) The bones would be less compressible.
- D
106) In compact bone, the osteons
A) are lined up in the same direction.
B) are lined up perpendicular to the long axis.
C) are arranged in an irregular pattern.
D) are separated by medullary spaces.
E) are lacking in the diaphysis.
- A
107) The trabeculae of spongy bone
A) are organized parallel to the long axis of the bone.
B) are organized along stress lines.
C) are composed mostly of cartilage.
D) will collapse under stress.
E) are concentrated in the cortex of the diaphysis.
- B
108) If the rate of osteolysis exceeds osteogenesis, bones will
A) grow. B) become thicker. C) become demineralized. D) become stronger. E) become calcified.
- C
109) When the epiphyseal plate is replaced by bone,
A) puberty begins. B) interstitial bone growth begins. C) appositional bone growth begins. D) long bones have reached their adult length. E) the bone becomes more brittle.
- D
110) When cartilage is produced at the epiphyseal side of the metaphysis at the same rate as bone is deposited on the opposite side, bones
A) grow longer. B) grow wider. C) become shorter. D) become more porous and weaker. E) become thicker.
- A
111) In normal adult bones,
A) there is no turnover of minerals.
B) a portion of the protein and mineral content is replaced each year.
C) osteoblast activity exceeds osteoclast activity, once bone has been formed.
D) osteoclasts continue to be active long after osteoblast activity ceases.
E) stresses will have no effect on the thickness of bone.
- B
112) _____ bone reduces the weight of the skeleton and makes it easier for muscles to move the bones.
A) Short B) Irregular C) Spongy D) Sesamoid E) Long
- C
113) The most abundant mineral in the body is
A) potassium. B) iron. C) phosphorus. D) calcium. E) sodium.
- D
114) The shaft of long bones is called the _____.
Answer: diaphysis
115) The head of a long bone is called the _____.
Answer: epiphysis
116) The _____ is the organic component of the bone matrix.
Answer: osteoid
117) Blood is distributed from the surface of a bone to deeper central canals by means of _____.
Answer: perforating canals
118) The region of a long bone where the epiphysis meets the diaphysis is known as the _____.
Answer: metaphysis
119) _____ prevents damaging bone-to-bone contact within movable joints.
Answer: Articular cartilage
120) During the process of _____, an existing tissue is replaced by bone.
Answer: ossification
121) The process of depositing calcium into a tissue is called _____.
Answer: calcification
122) Damage to a bone because of extreme load, sudden impact, or stresses applied from an unusual direction is called a(n) _____.
Answer: fracture
123) The adult skeleton contains _____ major bones.
Answer: 206
124) _____ _____ are remarkably stronger than steel.
Answer: Collagen fibers
125) _____ cells remove and recycle bone matrix.
Answer: Osteoclast
126) The matrix in spongy bone forms struts and plates called _____.
Answer: trabeculae
