Muscle Histology

Question 1

From tinyest to tendo name the structures of muscle

Answer 1

myofibril> muscle fiber > fascicle > muscle > tendons

Question 2

skeletal muscle morphology

Answer 2

long parallel cylinders
multiple peripheral nuclei
striations (contractile filaments)

skeletal muscle cells = muscle fibers

Question 3

skeletal muscle connections

Answer 3

fascicle bundles

tendons

Question 4

control of skeletal muscle

Answer 4

somatic motor neurons

voluntary control

Question 5

perimysium

Answer 5

sheath of connective tissue surrounding a bundle of muscle fibers

Question 6

endomysium

Answer 6

surrounds individual muscle fibers

Question 7

epimysium

Answer 7

surrounds muscle

Question 8

each muscle fiber contains several parallel bundles called

Answer 8

myofibrils

Question 9

each myofibril consists of a long series of

Answer 9

sarcomeres

Question 10

sarcomeres are seperated by

Answer 10

z discs

Question 11

the thin filaments (actin) are in the

Answer 11

Z DISC

Question 12

thick filaments (myosin) span:

Answer 12

the entire A band

Question 13

neuromuscular junction

Answer 13

junctions between nerve endings and muscle that are formed midway along the fiber

Question 14

motor endplate

Answer 14

modified area of the muscle fibre membrane at which a synapse occurs

Question 15

a motor nerve axon ending may have up to __ synaptic knobs but a single muscle fibre has only one endplate

Answer 15

50

Question 16

motor unit

Answer 16

number of muscle fibers innervated by a single neuron

Question 17

how many muscle fibers can a motor neuron innervate?

Answer 17

1-3 or as many as several hundred in major limb muscles

Question 18

depolarization oat the neuromuscular junction spreads internally via the

Answer 18

transverse tubule system

Question 19

where is calcium released form when it triggers contraction?

Answer 19

from the sarcoplasmic reticulum

Question 20

characteristics of smooth muscle

Answer 20

one nucleus per cell, located centrally
cell is elongated and spindle-shaped

much smaller than skeletal muscle cells

Question 21

does smooth muscle contain actin, myosin, and sarcomeres?

Answer 21

yes actin and myosin, no sarcomeres

Question 22

prominent locations of smooth muscle

Answer 22

wall of gi tract

walls of arteries and veins

Question 23

is smooth muscle capable of cell division?

Answer 23

yes

Question 24

smooth muscle cells are often connected via

Answer 24

gap junctions

Question 25

what type of innervation does smooth muscle receive?

Answer 25

both sympathetic and parasympathetic

Question 26

sympathetic innervation

Answer 26

supplied by spinal segments T1 to L3 of the thoracolumbar spinal cord

Question 27

parasympathetic innervation

Answer 27

supplied by the vagus and pelvic nerves

Question 28

what releases neurotransmitters?

Answer 28

varicosites

Question 29

cardiac muscle cells are joined end to end by

Answer 29

``` intercalated discs (intercellular junctions) - these provide electrical and mechanical coupling ```