CMN Flashcards
- A bundle of muscle fiber in the skeletal muscles is called: ________
a. Fasciculus
b. Myofilaments
c. Myofibrils
d. Sarcomere
a. Fasciculus
- Type Ia afferents in the muscle spindle is/are also known as:
a. Annulospiral nerve endings
b. Flowerspray nerve endings
c. Alpha motor neuron
d. Gamma motor neuron
e. A beta nerve fibers
a. Annulospiral nerve endings
- The following statement describes the principle of all or none law, EXCEPT:
a. Physiologic mechanism exist for fine gradation of the force of muscle contraction
b. The law applies only to individual motor units
c. All muscle fibers in a given motor unit contract or relax simultaneously
d. Activated muscle fibers contract maximally if the nerve activates the motor fibers of a motor unit sufficiently
e. In the same motor unit, it is possible for some muscle fiber to contract while others are relaxed
e. In the same motor unit, it is possible for some muscle fiber to contract while others are relaxed
- True about the myelin sheath:
a. Increases conduction velocity in large A beta and C fibers
b. Absent at the nodes of Ranvier thereby facilitating saltatory conduction
c. The Myelin sheath acts as a conductor of electricity
d. A and B
e. All of these are correct
b. Absent at the nodes of Ranvier thereby facilitating saltatory conduction
- Glial cell responsible for myelin production in the PNS
a. Oligodendrocytes
b. Ependydymal
c. Schwann cells
d. Microglia
e. Astrocytes
c. Schwann cells
- Generation of end plate potential in the sarcolemma of skeletal muscle is linked with
a. Voltage-gated channels
b. Ligand-gated channels
c. Mechanical-gated channels
d. Thermal-gated channels
b. Ligand-gated channels
- The connective tissue that covers individual muscle bundle:
a. Epimysium
b. Perineurium
c. Perimysium
d. Subcutaneous fascia
e. Endomysium
c. Perimysium
Code: Bundle ng pera (peri)
The portion between two Z-discs is called:
a. H zone
b. I band
c. A band
d. Y band
e. Sarcomere
e. Sarcomere
Code: ZarcomereZ
The plasma membrane of a skeletal muscle fiber is called:
a. Sarcoplasm
b. Sarcolemma
c. Sarcomere
d. Sarcoplasmic Reticulum
e. Neurolemma
b. Sarcolemma
Code: SacroLETAL muscle fiber
- Type of nerve fiber that has the fastest conduction:
a. Large myelinated axons
b. small myelinated axons
c. Small unmyelinated axon
d. large unmyelinated axon
a. Large myelinated axons
Code: Kapag malaki’t may cover, mabilis
The main neurotransmitter of the neuromuscular junction:
a. Calcium
b. Acetylcholine
c. Serotonin
d. Norepinephrine
e. Epinephrine
b. Acetylcholine
This thin filament has a high affinity for calcium:
a. Troponin I
b. Troponin C
c. Troponin T
d. Actin
e. Tropomyosin
b. Troponin C
C for calcium
Which among the following is the correct sequence for muscle contraction?
I. Action potentials arrive at the presynaptic terminal
II. Troponin C of the actin filament binds with Calcium
III. Acetylcholine is released in the synaptic cleft
IV. Power stroke occurs
V. ATP attaches to the myosin head
a. I II III IV V
b. I III II V IV
c. I II IV III V
d. I III II IV V
d. I III II IV V
- Location of the “triad” in skeletal muscles
a. At A-H junction
b. Along the Z line
c. At A-I junction
d. Along the M line
c. At A-I junction
- Which of the following does NOT properly describe a sarcomere?
a. The M line divides the A band
b. I band contains thin filaments
c. The H zone contains thin and thick filaments
d. Width of I band changes during contraction, A band does not
e. Actin filaments slide toward each other during contraction
c. The H zone contains thin and thick filaments
Only thick
Tandaan na kapag letter ‘H’, mukhang thick
- True of thin filaments:
a. Actin is the only thin filament
b. Consists of two heads: one is a binding site for ATP, the other is for the formation of cross bridges
c. Its backbone is a double stranded filamentous G actin, made of individual globular molecules called F actin
d. Tropomyosin spiral around the binding sites and attached intermittently are troponin molecules altogether forming a troponin-tropomyosin complex
e. None of these
d. Tropomyosin spiral around the binding sites and attached intermittently are troponin molecules altogether forming a troponin-tropomyosin complex
- In comparing electron micrographs of a relaxed skeletal muscle fiber and a fully contracted muscle fiber which would be seen only in the relaxed fiber?
a. Z lines
b. Triads
c. Myosin
d. A bands
e. H zones
e. H zones
Thick kaya kita pa rin
- Which of the following generates the lowest tension?
a. Fast concentric
b. Slow concentric
c. Fast eccentric
d. Slow eccentric
e. Isometric
a. Fast concentric
- Skeletal muscle contraction stops when:
a. ATP is released from myosin
b. Decreased concentration of intracellular calcium ions
c. Ionization of cell
d. Sodium pump reversal
e. Depolarization of the cell
b. Decreased concentration of intracellular calcium ions
- Which of the following muscle is involuntary non-striated?
a. Cardiac and smooth muscles
b. Cardiac muscles
c. Skeletal and cardiac muscles
d. Smooth muscles
d. Smooth muscles
- “Cell Drinking mechanism”
a. Osmosis
b. Diffusion
c. Phagocytosis
d. Pinocytosis
e. Active transport
d. Pinocytosis
Code: pINOM cytosis
- The physiologic property unique to muscle cells is due to the presence of which of the following?
a. Ligand-gated channels
b. Terminal endings
c. Myofilaments
d. Sarcolemma
c. Myofilaments
- Source of calcium in skeletal muscle contraction?
a. Exocytosis from the vesicle to synaptic cleft
b. Release from sarcoplasmic reticulum to sarcoplasm
c. Efflux from cisterns of sarcoplasmic reticulum to extracellular area
d. Sarcolemma after exocytosis from the sarcoplasm
b. Release from sarcoplasmic reticulum to sarcoplasm
- What type of transport process is involved when sodium is transported into the cell in exchange for calcium?
a. Vesicular transport
b. Primary active transport
c. Passive transport
d. Secondary active transport
d. Secondary active transport
- Rate of diffusion is fasted in/for:
a. Gases like O2 and CO2
b. A solid medium
c. A membrane that is 1 micrometer thick
d. 2 solutions having equal solute concentration
a. Gases like O2 and CO2
- The potassium leak channels are:
a. Markedly affected by electrical gradient or electrostatic forces when a cell is polarized
b. Transporting ions without control or regulation
c. Capable of promoting potassium influx
d. Not active during the repolarization of the action potential
b. Transporting ions without control or regulation