The muscular system is essential for body movement, with three main types of muscle: skeletal, cardiac, and smooth. Skeletal muscles, which constitute 40-50% of body weight, facilitate functions such as locomotion, posture maintenance, respiration, and heat production. Key characteristics of skeletal muscle include multinucleate cells, striated appearance, and voluntary control, surrounded by connective tissue wrappings.

1. MUSCULAR SYSTEM
PRESEENTED BY : Ms.Sapna Rani
MMCP,MM(DU)
ASSISTANT PROFESSOR
PHARMACOLOGY

2. The Muscular System
 Muscles are responsible for all types of body
movement – they contract or shorten and are the
machine of the body
 Three basic muscle types are found in the body
Skeletal muscle
Cardiac muscle
Smooth muscle
Slide 6.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

3. Introduction
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 Human body contains over 400 skeletal muscles
 40-50% of total body weight
Functions of skeletal muscle
 Body movement (Locomotion)
 Maintenance of posture
 Respiration
 Diaphragm and intercostal contractions
 Communication (Verbal and Facial)
 Constriction of organs and vessels
 Peristalsis of intestinal tract
 Vasoconstriction of b.v. and other structures
(pupils)
 Production of body heat (Thermogenesis)

4. Skeletal Muscle Characteristics
• Most are attached by tendons to bones Cells are
multinucleate
• Striated – have visible banding Voluntary – subject to
conscious control
• Cells are surrounded and bundled by connective tissue =
great force, but tires easily

5. Terms
Sarcolemma = Cell membrane
Sarcoplasm = Cytoplasm
Sarcoplasmic Reticulum =
Endoplasmic Reticulum
Sarcosomes = Mitochontria
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6. Connective Tissue Wrappings of
Skeletal Muscle
Slide 6.4a
Endomysium –
around single
muscle fiber
Perimysium –
around a
fascicle
(bundle) of
fibers
Figure 6.1

7. Connective Tissue Wrappings of Skeletal
Muscle
Epimysium –
covers the
entire skeletal
muscle
Fascia – on the
outside of the
epimysium
Figure 6.1