EDSS 541 RR2

1. Our ITU team consists of myself for Biology, Pilar Sanchez for Math, and Brianna Murdoch for PE. The sources that our ITU team referred to included the National Standards for PE specifically, weight lifting. Physiology, specifically the muscular system and for Algebra, Equations, specifically linear equations. We all agreed that this would make sense how all three subjects can enhance each other with further understandings about health and the muscular system.
We are individually planning our unit to the State Frameworks under our disciplines, then using our CT's resources and textbooks at La Costa Canyon High School for lesson activities.

2.  Visual Web of Muscular System

 KEY POINTS

I. Review muscular system

A. Types of muscles

1. Skeletal

2. Smooth

3. Cardiac

B. Structure of muscles

1. Fibers

2. Myofibrils

a. Striated – I bands and A bands make up the sarcomere.

b. Unstriated

3. Neuromuscular junction

4. Motor units

II. Muscle contraction – depends on several cellular and chemical processes to make the myofibrils move.

A. Contractile Proteins

1. Thin filaments

a. actin

b. tropomyosin

c. troponin

2. Thick filaments – The myosin molecule has a “head” and a “tail”.

III. Molecular basis of contraction

A. Sliding filament theory – Individual sarcomeres shorten when the muscle contracts.

B. Crossbridge cycle – Actin binds to myosin and forms a “crossbridge” (linkage) shortening the muscle fiber.

C. Regulatory proteins and calcium

1. Tropomyosin and troponin inhibit actin from binding to myosin.

2. Calcium allows actin to form a crossbridge with myosin

3. Dystrophin supports the sarcolemma against the forces of contracting. Prevents Duchenne Muscular Dystrophy

D. Stimulus for contraction

1. Depends on a neurotransmitter diffusing across the synaptic cleft causing a muscle impulse .

2. The muscle impulse causes the release of calcium from the sarcoplasmic reticulum.

E. Energy sources for contraction

1. ATP – is the immediate source of energy but it is only found in small amounts in muscle.

2. Creatine phosphate –

a. Stores high energy bonds that can be used to make ATP

b. present in muscles four to five times the concentration of ATP

IV. Mechanics of muscle contraction

A. Types of contractions

1. isotonic – the muscle shortens

2. isometric (static)

a. the muscle develops tension but does not shorten.

b. the heart must work harder because little vasodilation takes place in the periphery.

B. Neural systems at work when muscles are exercised.

1. “Central command” located in the higher centers in the brain and is responsible for heart rate and strength of contraction..

2. Feedback mechanism which monitors the buildup of cellular waste and signals the brainstem to increase cardiac output.

C. Twitch

D. Tetanus

V. Muscle fatigue – The inability of a muscle to contract (maintain tension).

A. build up of lactic acid

B. lack of ATP

C. lack of blood flow to muscle

Resource: http://www.haspi.org/curriculum-library/A-P-Core-Labs/05%20Muscular%20System/Labs%20&%20Activities/Activity%20-%20Muscle%20Fatigue.pdf

7.2 Possible Essential Questions:
1. How does your health connect to your performance and success at school?
2. How many calories can my specific body process in order to maintain a healthy weight?
3. How can weight training connect to a healthy lifestyle?
4. How does the structure of the muscles relate to muscles function?
5. How can muscles be a useful tool to maintain a healthy lifestyle?
6. How can calorie counting management be a useful tool to stay healthy?
7. How can algebra be incorporated into muscle building exercises?
8. How can the understanding of the muscular system contribute to effective muscle building?