Smooth Muscles

SMOOTH MUSCLES Smooth muscle is non striated and INVOLUNTARY .Muscle fibers in smooth muscle are spindle shaped and are uninucleated (single nucleus). It is found in the walls of blood and lymph vessels, the alimentary tract, the respiratory tract, the urinary bladder and the uterus

Multiple Choice Questions 1 A neuron has following parts except a) Nerve cell body b) Dendrites c) Axons d) Glial cells

2 Receptive processes of neurons are a) Nerve cell body b) Dendrites c) Axons d) Synaptic knob

3 Myelinated nerves a) Are all preganglionic fibers of ANS b) Nerve fibers have less than 1 micron diameter c) Conduction is slower than unmyelinated nerves d) Axons are surrounded by Schwann cells without wrapping of myelin

a) b) c) d)

4 Myelin is formed in CNS around axons by Microglia Astrocytes Oligodendroglia None of the above

5 Following nerve fiber is least susceptible to hypoxia a) A fibers b) B fibers c) C fibers d) None

6 Following is most sensitive to local anesthetic a) A fibers b) B fibers c) C fibers d) None

7 Maximum conduction of velocity in unmyelinated nerve fiber is a) 0.5 m/sec b) 1m/sec c) 2 m/ sec d) 4 m/ sec

8 Not true about acetylcholine is a) Synthesised in mitochondria within the cell b) Destroyed by acetylcholine esterase in post synaptic cleft

c) Responsible for synaptic transmission d) Ach receptors are present on presynaptic membranes

9 RMP of skeletal muscle membrane is a) 70 mV b) 80 mV c) 85 mV d) 90 mV

10 Intercalated discs are present in a) Smooth muscle b) Skeletal muscle c) Cardiac muscle d) Nerve fibers

11 Voluntary muscle is a) Skeletal muscle b) Smooth muscle c) Cardiac muscle d) None

12 Light and dark bands in skeletal muscle are a) A and I bands respectively b) I and A bands respectively c) H zone and Z line respectively d) Z line and H zone respectively