Is smooth muscle a single unit?
Single-unit smooth muscle is found in the walls of hollow organs; multiunit smooth muscle is found in airways to the lungs and large arteries. Single-unit smooth muscle cells contract synchronously, they are coupled by gap junctions, and they exhibit spontaneous action potential.
Which are characteristics of single unit smooth muscles quizlet?
-Single unit smooth muscle possess myogenic activity: Originating from the muscle cells and self-excitable. -Unstable resting membrane potential usually set at -50 to -60 mV (30 mV less negative than skeletal muscles). Spontaneous pacemaker activity: Slow depolarization due to permeability changes in ions.
What is a single smooth muscle cell called?
Smooth muscle cells known as myocytes, are spindle-shaped with a wide middle and tapering ends, and like striated muscle, can tense and relax. In the relaxed state, each cell is 30–200 micrometers in length.
What is the functional unit of smooth muscle?
The primary smooth muscle structural and functional unit – the smooth muscle myocyte ( Myocytus nonstriatus) has unique structure, arrangement and innervation. The spindle shape of the mononucleated smooth muscle cell permits a close contact among cells in the splanchnic and vascular walls.
How do single unit and multiunit smooth muscle differ in innervation and contractile behavior?
With innervation, multiunit smooth muscle is automatic, and its contractile behavior responses to variable (graded) electrical changes in the sarcolemma or even in the absence of electrical excitation. Single-unit smooth muscle has a innervation that are electrically coupled to each by gap junctions from myocytes.
Which of these locations in the body contains single unit smooth muscle quizlet?
single-unit smooth muscle is found in the walls of hollow organs; multiunit smooth muscle is found in airways to the lungs and large arteries.
What is the function of smooth muscle quizlet?
Explanation: Smooth muscle cells are responsible for involuntary movements like regulation of blood flow through vital organs and movement of materials along digestive and urinary passageways.
Which of the following describes the cells of single unit visceral muscle?
The correct answer: The cells of single-unit visceral muscle C) exhibit spontaneous action potentials.
How does smooth muscle differ from skeletal muscle?
Cardiac and skeletal muscle are both striated in appearance, while smooth muscle is not. Both cardiac and smooth muscle are involuntary while skeletal muscle is voluntary. Striated muscle contracts and relaxes in short, intense bursts, whereas smooth muscle sustains longer or even near-permanent contractions.