Arrangement of Fascicles MELANIE HERRERA fascicles A fascicle

fascicles A fascicle is several sheathed muscle fibers wrapped by a coarse fibrous membrane

Circular When fascicles are arranged in concentric rings (sphincters) Circular muscles are typically found

Convergent When the fascicles converge to a single insertion Triangular or fan-shaped A broad

Parallel The length of the muscle runs parallel to the long axis of the

Pennate Short fascicles Attach obliquely to a central tendon Three type of forms: Unipennate

unipennate insert into one side of the tendon fibers angled on 1 side of

Bipennate inserts into opposite sides of the tendon fibers angled on both sides of

multipennate inserts into multiple places of the tendon branches within muscle A muscle with

Overview Your text here Different types of fascicles and where they can be found.

Question 1 Sphincter muscles consist of which arrangement of fascicles? A. parallel B. Circular

Question 2 When the arm is flexed, the biceps brachii bulges in the middle.

Question 3 Muscle fibers are bundled into groups known as A myotendrils B endomysium

Bibliography “Muscle mechanics: Fascicle arrangement. ” Muscular. Anatomy & Physiology, 11 July 2014. Web.

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Arrangement of Fascicles MELANIE HERRERA

fascicles A fascicle is several sheathed muscle fibers wrapped by a coarse fibrous membrane Different types Circular Convergent Parallel Pennate Unipennate Multipennate Fusiform Bipennate

Circular When fascicles are arranged in concentric rings (sphincters) Circular muscles are typically found surrounding external body opening which they close by contracting Examples are the orbicularis muscles surrounding the eyes and the mouth.

Convergent When the fascicles converge to a single insertion Triangular or fan-shaped A broad area converges on attachment site (tendon, aponeurosis, or raphe) Muscle fibers pull in different depending on stimulation directions,

Parallel The length of the muscle runs parallel to the long axis of the muscle Strap like. Fibers parallel to the long axis ofmuscle Most skeletal muscles are arranged this way The center or body of the muscle thickens when parallel muscle contracts Parallel muscles contract extensively However, some scientists classify spindle-shaped muscles into a separate class as fusiform muscles.

Pennate Short fascicles Attach obliquely to a central tendon Three type of forms: Unipennate Bipennate multipennate • Pennate = “feather-like” • Form an angle with the tendon • Do not move as far as parallel muscles • Contain more myofibrils than parallel muscles • Develop more tension than parallel muscles

unipennate insert into one side of the tendon fibers angled on 1 side of tendon – e. g. , extensor digitorum

Bipennate inserts into opposite sides of the tendon fibers angled on both sides of tendon – e. g. , rectus femoris

multipennate inserts into multiple places of the tendon branches within muscle A muscle with several tendons of origin and several tendons of insertion, in which fibers pass obliquely from a tendon of origin to a tendon of insertion on each side e. g. , deltoid

Overview Your text here Different types of fascicles and where they can be found. Video presentation https: //www. youtube. com/watch? v=Fh YPCQ 0 Ix 9 E

Question 1 Sphincter muscles consist of which arrangement of fascicles? A. parallel B. Circular C. Pennate Answer A

Question 2 When the arm is flexed, the biceps brachii bulges in the middle. This type of muscle consists of _____ fascicles A. Parallel B. circular C. Pennate Answer C

Question 3 Muscle fibers are bundled into groups known as A myotendrils B endomysium C myosin D. fascicles Answer D

Bibliography “Muscle mechanics: Fascicle arrangement. ” Muscular. Anatomy & Physiology, 11 July 2014. Web. 15 Dec. 2016. Marieb, Elaine Nicpon N. Essentials of Human Anatomy and Physiology. 9 th ed. San Francisco: Benjamin-Cummings Publishing Company, Subs of Addison Wesley Longman, 2009. Print. Dr. Lorena Canelon. “ 1. Arrangement of Fascicles in Muscles. ” You. Tube, 21 June 2016. Web. 15 Dec. 2016.