Explanation Rectus muscles, as the name suggests, refer to ‘straight muscles’ and they describe not only the position of these muscles in the body, but also the actions they perform. The rectus muscles are superior rectus, inferior rectus, medial rectus, and lateral rectus muscles, and out of which, ...

Human Anatomy & Physiology (2nd Edition)

2nd Edition

ISBN: 9780134553511

Author: Erin C. Amerman

Publisher: PEARSON

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Question

Chapter 9.2, Problem 6QC

Summary Introduction

To review:

The extrinsic eye muscles that pull the eyeball superiorly and inferiorly.

Introduction:

There are six skeletal muscles, collectively called extrinsic eye muscles, that help in the movement of the eye. Out of these, there are four ‘rectus’ muscles (straight line movement) that are responsible for eyeball movement.

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Chapter 9.2, Problem 5QC

Chapter 9.2, Problem 7QC

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Chapter 9 Solutions

Human Anatomy & Physiology (2nd Edition)

Ch. 9.1 - What is a fascicle, and how does it relate to the...Ch. 9.1 - 2. How do the terms pennate, parallel, and...Ch. 9.1 - The adductor magnus muscle is a muscle in the...Ch. 9.1 - 4. What is the role of an agonist in a muscle...Ch. 9.1 - What are a muscles origin and insertion, and how...Ch. 9.1 - 6. How do first-, second-, and third-class lever...Ch. 9.2 - 1. How do the muscles of facial expression differ...Ch. 9.2 - Which muscles are involved in opening and closing...Ch. 9.2 - What are three muscles involved in producing happy...Ch. 9.2 - Which muscles are involved in producing frowning...

Ch. 9.2 - Which extrinsic eye muscles pull the eyeball...Ch. 9.2 - Prob. 6QC Ch. 9.2 - Prob. 7QC Ch. 9.2 - Prob. 8QC Ch. 9.2 - Prob. 9QC Ch. 9.2 - What are the three main muscles of the erector...Ch. 9.2 - 11. What additional roles besides supporting...Ch. 9.3 - What is the main muscle of inspiration, and where...Ch. 9.3 - What roles do the external and internal...Ch. 9.3 - Which muscles are involved in trunk flexion?Ch. 9.3 - Prob. 4QC Ch. 9.3 - Prob. 5QC Ch. 9.3 - Prob. 6QC Ch. 9.4 - Prob. 1QC Ch. 9.4 - Which posterior trunk muscles act on the scapula?...Ch. 9.4 - Prob. 3QC Ch. 9.4 - 4. What are two muscles that adduct the arm? Ch. 9.4 - Prob. 5QC Ch. 9.4 - Prob. 6QC Ch. 9.5 - Prob. 1QC Ch. 9.5 - Prob. 2QC Ch. 9.5 - Prob. 3QC Ch. 9.5 - Prob. 4QC Ch. 9 - Which type of muscle fascicle pattern has an...Ch. 9 - 2. If “adductor” is part of the name of a muscle,...Ch. 9 - Match the term with its description: _____Brevis...Ch. 9 - Prob. 4CYR Ch. 9 - 5. Which function is being fulfilled by a muscle...Ch. 9 - Prob. 6CYR Ch. 9 - Which eye muscle passes through the trochlea and...Ch. 9 - Prob. 8CYR Ch. 9 - Prob. 9CYR Ch. 9 - Prob. 10CYR Ch. 9 - 11. Match the muscle with its main...Ch. 9 - Prob. 12CYR Ch. 9 - Prob. 13CYR Ch. 9 - Prob. 14CYR Ch. 9 - Prob. 15CYR Ch. 9 - Prob. 16CYR Ch. 9 - Prob. 1CYU Ch. 9 - Prob. 2CYU Ch. 9 - Prob. 3CYU Ch. 9 - Prob. 4CYU Ch. 9 - Prob. 5CYU Ch. 9 - The rectus femoris muscle originates from the...Ch. 9 - Prob. 1AYKA Ch. 9 - Prob. 2AYKA Ch. 9 - Prob. 3AYKA Ch. 9 - Prob. 4AYKA Ch. 9 - Prob. 5AYKB

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Solution Summary: The author explains that the rectus muscles, as their name suggests, perform their respective functions and actions of moving the eyeball medially and laterally.

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