Muscles
- Muscles is a contractile tissue which brings about movements.
- Muscles can be regarded as motors of the body.
Derivation of Name
Muscles (L. Mus = mouse) are so named because, many of them
resemble a mouse, with their tendons representing the tail.
Types of muscles
The muscles are of three types, skeletal, smooth and cardiac.
(A) Striated muscles/ Skeletal muscles :-
- Striated muscles are present in the limbs, body wall, tongue, pharynx, and beginning of oesophagus.
- Long and cylindrical.
- Fibres and unbranched.
- Multinucleated.
- Bounded by sarcolemma.
- Light and dark bands present.
- No intercalated disc.
- Nerve supply from cranial nervous system.
- Blood supply is abundant.
- Very rapid contraction.
- They soon get fatigued.
- Voluntary.
(B) Non- Striated muscles/ Smooth muscles :-- Oesophagus (Distal part), urogenital tract, urinary bladder, blood vessels, iris of eye, arrector pilli muscles of hair.
- Spindle shaped.
Fibre unbranched.- Uninucleated.
- Bounded by Plasmalemma.
- Light and dark bands absent.
- No intercalated discs.
- Nerve supply from autonomic nervous system.
- Blood supply is scanty.
- Slow contraction.
- They don't get fatigued.
- Involuntary.
(C) Cardiac muscles :-


- Wall of heart.
- Short and cylindrical.
- Fibres branched.
- Uninucleated.
- Bounded by plasmalemma.
- Faint light and dark bands present.
- Intercalated disc present and a
characteristic feature.
- Nerve supply from autonomic nervous system.
- Blood supply
is abundant.
- Rapid contractions.
- They never get fatigued.
- Involuntary