BIOL235 Chapter 11 Exam Questions and Answers 100% Pass

BIOL235 Chapter 11 Exam Questions and Answers 100% Pass origin - The attachment of a muscle's tendon to the stationary bone insertion - the attachment of the muscle's other tendon to the movable bone belly (body) - the fleshly portion of the muscle between the tendons actions - the main movements that occur when the muscle contracts. reverse muscle action - during specific movements of the body the actions are reversed; therfore, the positions of the origin and insertion of a specific muscle are switched. lever - a rigid structure that can move around a fixed point fulcrum - a fixed point in a lever 2 100% Pass Guarantee Katelyn Whitman, All Rights effort - causes the movement. Is the force exerted by muscular contraction. Load (or resistance) - opposes movement. Typically the wietght of the body part that is moved or some resistance that the body is trying to overcome (such as the weight of a book you might be picking up). Mechanical advantage - if the load is closer to the fulcrum and the effort is farther from the fulcrum, then only a relatively small effort is needed to move a large load over a small distance. Mechanical disadvantage - if the load is farther from the fulcrum and the effort is applied closer to the fulcrum, then a relatively large effort is required to move a small load (but at greater speed) First class levers - EFL - falcum is between the effort and the load. Can produce either a mechanical advantage or disadvantage depending on whether the effort (mechanical disadvantage) or the load (mechanical advantage) is closer to the falcrum. Second class levers - ELF - load is between the fulcrum and the effort. 3 100% Pass Guarantee Katelyn Whitman, All Rights Always produce a mechanical advantage because the load is always closer to the falcrum than the effort. This arrangement sacrifices speed and range of motion for force. Thus, this type of lever produces the most force. Third class levers - FEL - effort is between the fulcrum and the load. Most common lever in the body. Always produce a mechanical disadvantage because the effort is always closer to the falcrum than the load. This arrangement favors speed and range of motion over force. prime mover (or agonist) - one of the opposing muscle pairs at the joints that contracts to cause an action. Example: biceps brachii in flexing the forearm. antagonist - the other opposing muscle pairs that stretches and yields to the effects of the prime mover Example: triceps brachii in flexing the forearm What happens if prime mover and its antagonsit attracts at the same time with equal force? - No movement is produced. 4 100% Pass Guarantee Katelyn Whitman, All Rights synergist - muscles prevents unwanted movement at intermediate joints or to otherwise aid the movement of the prime mover muscle by contracting and stabilizing the intermediate joint. Synergists are usually located close to the prime mover. fixator - stabilizing the origin of the prime mover so that the prime mover can act more efficiently. Fixators steady the proximal end of a limb while movements occur at the distal end. compartment - a group of skeletal muscles, their associated blood vessels, and associated nerves, all of which have a common function. Example: flexor compartment muscles (anterio