Chapter 6 MuscularSystem

Types of Muscle SkeletalSmoothCardiac

Questions Answer questions #1 and 2 on page 158 and #19 on page 158.

Functions Movement Posture (muscle tone) Heat production

Movement A. Involuntary (Smooth muscles and cardiac muscle) 1.Found in digestive tract, blood vessels, ureters, heart 2.No striations (stripes); appears smooth 3.Peristalsis (digestive tract) 4.Intercalcated discs (heart)

Movement B. Voluntary 1.Found in skeletal system 2.Skeletal muscle is stimulated by the nervous system, moving two bones closer together 3.The movement occurs at the joint

Movement (cont) Muscles attach in groups to move bones at the joint Origin bone and insertion bone Muscles move the insertion bone toward the origin bone I to O

Insertion/origin example Remember; I to O A muscle originates at a relatively stable part of the skeleton (origin) and inserts at a skeletal part that is moved when the muscle contracts (insertion) Biceps muscle; Origin (stable) Head of humerus Origin (stable) Head of humerus Insertion (mover) Radius Insertion (mover) Radius When biceps contracts (shortens) the radius moves toward the humerus the radius moves toward the humerus TRY IT!!! TRY IT!!!

Muscular Movement Generally smooth and not jerky (muscles generally work in groups) (muscles generally work in groups) Also controlled in the amount of movement (4 types of contraction) Twitch,tetanic, isotonic, isometric Controlled by the nervous system

Muscle Groups Prime mover (main contracting muscle responsible for the movement) (main contracting muscle responsible for the movement)Synergist (other muscles that help produce the movement) (other muscles that help produce the movement)Antagonist (relax during contraction) (relax during contraction)

Example Group; biceps brachii, brachialis, and triceps brachii Function: bending and straightening the the forearm at the elbow BENDING; prime: biceps brachii synergist: brachialis synergist: brachialis antagonist: triceps antagonist: triceps relaxes relaxes

Straightening of the Forearm Same 3 muscles Prime: triceps Prime: triceps Synergist: none Synergist: none Antagonist: biceps and brachialis Antagonist: biceps and brachialis

Questions Answer questions #11-14 on page 158.

Posture Counteracting the pull of gravity Gravity tends to pull the trunk and head down and forward Tonic contractions of back and neck muscles hold the head and trunk erect Good posture hold body parts in corect position/alignment which prevents stress and injury to other parts/organs

Tonic Contractions In the large muscle, a few fibers shorten at one time The muscle as a whole does not shorten No movement occurs A pull against gravity (posture) does occur

Heat Production Constant body temperature Contraction of muscle fibers produces most of our body heat Questions What is a fever? Hypothermia? When are these useful? When can they be harmful?

Types of Skeketal Muscle Contraction TwitchTetanicIsotonicIsometric

Definitions Research each type of contraction on page on page 164 in your text Name two types of exercise that would be isotonic and two isometric What type of workout would best benefit you and why

Effects of Exercise Define the following: 1.Atrophy 2.Hypertrophy 3.Strength training 4.Endurance training 5.Aerobic training

Write an Exercise Prescription Write an exercise prescription for: 1.A person who had a heart attack 2.A dancer 3.A runner 4.An elderly person (PICK ONE) (PICK ONE) Include type, duration and frequency and benefits

Question What other body system(s) assist in coordination of the muscular system? Go on the internet and research one of the following: 1.) myastenia gravis 1.) myastenia gravis 2.) quadraplegia 2.) quadraplegia 3.) muscle strain 3.) muscle strain 4.) low back pain 4.) low back pain 5.) muscular dystrophy 5.) muscular dystrophy

Assignment Define what occurs with this disease What are the symptoms What are the causes What is the treatment Is it preventable Make this a typed word document to hand in at the end of class