Muscle Structure

Type of Skeletal Cardiac Smooth
Muscle
Fibre Striated. Specialised Non-striated.
Appearance striated.
Controls Involuntary Involuntary (autonomic NS).
Voluntary (somatic (autonomic NS). Diameter of arteries/
NS). Contraction of arterioles/ bronchi/
Movement of heart bronchioles.
skeleton. (myogenic). Control of Peristalsis/ uterine
contractions/ pupil size.
Arrangement Cells branch and
Regular – muscle interconnect, No regular arrangements –
contracts in one resulting in different cells can contract in
direction. simultaneous different directions.
contraction.
Contraction Fast twitch: rapid. Intermediate Slow.
Speed Slow twitch: slow. (rhythmic).
Length of Fast twitch: short. Intermediate Relatively long.
Contraction Slow twitch: long. (rhythmic).
Structure Faint stripes on
Tubular, striated the fibres. Fibres
fibres with Fibres are spindle shaped and
are branched an uninucleated.
multinucleate uninucleated.
cells. Intercalated
discs present.
Found In Limbs & Bronchi/ bronchioles/
intercostal Walls of heart. arteries/ arterioles/
muscles. oesophagus/ gut.