Muscular System of Vertebrates ABOUT THE AUTHOR Seth M. Kisia is an associate professor and Daniel W. Onyango is a senior lecturer in the Department of Veterinary Anatomy, University of Nairobi. The authors have been involved in teach- ing anatomy to students of veterinary, agriculture, environmen- tal health, biochemistry and biomedical technology as well as courses in mammalogy and ichthyology to wildlife students. The authors have also been involved in conducting research in reproductive biology, and muscular and respiratory systems for several years. Muscular System of Vertebrates Seth M. Kisia Department of Veterinary Anatomy University of Nairobi Nairobi, Kenya Daniel W. Onyango Department of Veterinary Anatomy University of Nairobi Nairobi, Kenya Science Publishers, Inc. Enfield (NH), USA Plymouth, UK CIP data will be provided on request. SCIENCE PUBLISHERS, INC. Post Office Box 699 Enfield, New Hampshire 03748 United States of America Internet site: http://www.scipub.net [email protected] (marketing department) [email protected] (editorial department) [email protected] (for all other enquiries) ISBN 1-57808-306-0 © 2005 Copyright reserved All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior written permission. This book is sold subject to the condition that it shall not, by way of trade or otherwise, be lent, re-sold, hired out, or otherwise circulated without the publisher’s prior consent in any form of binding or cover other than that in which it is published and without a similar condition including this condition being imposed on the subsequent purchaser. Published by Science Publishers, Inc. Enfield, NH, USA Printed in India Acknowledgements The authors acknowledge the artistic expertise of Amos T. Mwasela and technical assistance of Irene Nyamoita, both of the Department of Veterinary Anatomy, University of Nairobi, Kenya. Contents Acknowledgements v 1. General Introduction to Vertebrate Muscular System 1 The Muscular System 3 Muscle Contraction 6 Tonic and Phasic Muscles 6 Development and Evolution of the Muscular System 8 Fish Muscular System 9 Classes of Vertebrates 9 Jawless Fishes (Class Agnatha) 10 Jawed Fishes (Gnathostomes) 11 Placoderms 12 Chondrichthyes 13 Osteichthyes 14 Tetrapod Muscular System 17 Amphibians 17 Reptiles 18 Birds 20 Mammals 23 2. Muscle Types 26 Introduction 26 Smooth Muscles 27 Cardiac Muscles 28 Intercalated Disks 30 Impulse Generation and Conduction in Cardiac Muscles 30 Skeletal Muscles 31 Fiber types 31 (cid:1)(cid:2)(cid:2)(cid:2) (cid:3)(cid:4)(cid:5)(cid:6)(cid:4)(cid:7)(cid:8)(cid:9)(cid:10)(cid:10)(cid:5)(cid:11)(cid:5)(cid:12)(cid:13)(cid:3)(cid:10)(cid:14)(cid:15)(cid:10)(cid:16)(cid:13)(cid:9)(cid:12)(cid:13)(cid:17)(cid:9)(cid:8)(cid:12)(cid:13)(cid:5) Tonic Muscle Fibers 32 Slow Phasic (Red) Fibers 32 Fast Phasic (White) Fibers 33 Intermediate Phasic (Pink) Fibers 33 Motor Unit 34 Accessory structures associated with Muscle 34 Fasciae 34 Synovial Bursae 35 Tendon Sheaths 35 Muscle Pennation 35 Skeletal Muscle Movements and Functions 36 Muscle groups in Vertebrates 37 (i) Cutaneous Muscles 37 (ii) Muscles of Facial Expression 37 (iii) Muscles of Mastication 39 (iv) Hyoid Muscles 39 (v) Extrinsic Muscles of the Tongue 39 (vi) Intrinsic Muscles of the Tarynx 40 (vii) Muscles of the Neck 40 (viii) Muscles of the Thoracic Girdle 41 (ix) Muscles of the Thorax 41 (x) Muscles of the Abdominal Wall 42 (xi) Epaxial Muscles of the Back 42 (xii) Muscles of the Tail 42 (xiii) Sublumbar Muscles 43 (xiv) Muscles of the Shoulder 43 (xv) Muscles of the Elbow Joint 43 (xvi) Rotators of the Forearm 44 (xvii) Muscles of the Carpal Joint 44 (xviii) Muscles of the Digits 44 (xix) Outer Hip and Croup Muscles 45 (xx) Coudolateral Muscles of the Thigh (Muscles of the Buttocks) 45 (xxi) Medial Muscles of the Thigh 45 (xxii) Deep Muscles of the Hip Joint 45 (xxiii) Special Muscles of the Stiffle Joint 45 (xxiv) Muscles of the Hock Joint 46 (xxv) Muscles of the Digits 46 (cid:6)(cid:14)(cid:18)(cid:12)(cid:13)(cid:18)(cid:12)(cid:5) (cid:19)(cid:20) 3. Muscle Development 47 Origin of Muscle Cells 47 Origin of Vertebrate Musculature 47 Smooth Muscles 48 Cardiac Muscles 48 Skeletal Muscles 49 Muscles of the Head 49 Muscles of the Neck and Trunk 50 Muscles of the Limb 52 4. Muscle Contraction 53 Sarcomeric Structure 53 Contractile Proteins 55 Actin 55 Myosin 56 Tropomyosin 57 Troponin 57 Actinin 57 Mechanism of Muscle Contraction 58 Skeletal Muscles 58 Smooth Muscle 58 Regulation of Muscle Contraction 59 Skeletal Muscles 60 Cardiac Muscle 60 Smooth Muscles 61 Muscle Relaxation 62 Temperature and the Sliding Filament Mechanism 62 Types of Muscle Contraction 63 Isometric Contractions 63 Isotonic Contractions 63 Negative Work Contractions 64 Muscle Fatigue 64 Rigor Mortis 64 Shortening and Power Output of Muscles 65 5. Body Support in Vertebrates 66 Swimming 66 Fish Swimming 67 Fish Swimming Movements 68