Smooth muscle arrangement

Question 1

What are the two types of arrangements for smooth muscle?

Answer 1

1. Visceral (unitary, syncytial, single-unit)

2. Multi-unit

Question 2

How is visceral smooth muscle arranged?

Answer 2

single sheet of interconnected cells that contract simultaneously

Question 3

How is multi-unit smooth muscle arranged?

Answer 3

Individual smooth muscle cells, separated from each other by a thin membrane, each receiving its own innervation

Question 4

How are visceral muscle cells connected?

Answer 4

gap junctions - transmit action potentials between cells

Question 5

How are multi-unit muscle cells connected?

Answer 5

They aren’t.

Question 6

Where would one find visceral muscle?

Answer 6

hollow organs: stomach intestines, uterus, bile duct, bladder, most blood vessels

Question 7

Where would one find multi-unit muscle?

Answer 7

constrictor and dilator muscles of iris, arrector pili muscles, pulmonary air passages and walls of LARGEST arteries

Question 8

What type of muscle would you find in the Aorta?

Answer 8

Multi-unit muscle

Question 9

T/F Most organs have 2 layers of visceral muscles, one running longitudinally, one running transversely.

Answer 9

True. Exception being the stomach which has an additional layer (3 total) running obliquely to the other two.