The Muscular System

1. The Muscular System

2. Muscular System: is a collection of organs whose primary function is movement. • Organs in this system include the muscles and the connective tissue that attaches them to bones.

3. Three types of muscle: • Smooth • Cardiac • Skeletal

4. Smooth muscle: is the type of muscle found in the blood vessels and the digestive tract.

5. Cardiac Muscle: (card = heart) the type of muscle found in the heart.

6. Skeletal Muscle: the type of muscle that moves bones and helps protect inner organs.

7. Look at slides under microscope.

8. Muscle action • Voluntary • Involuntary

9. Voluntary muscle movement: Muscle action that is under your control. • Flexing

10. Involuntary Muscle Movement: Muscle action that is not under your control. You don’t think about it, it just happens. • Digestive muscles • Heart muscles • Blinking your eyes can be both.

11. Muscle Movement • Electrical signals travel from the brain to your muscles. The cells respond by contracting or releasing.

12. Tendons: Tough connective tissue that connects your muscles to your bones.

13. Muscle usually works in pairs: • Flexor: Allows your muscles to bend • Extensor: Allows your muscles to straighten. • In your arm • Biceps: is the flexor • Triceps: is the extensor

14. When muscles contract blood vessels in the muscle get squeezed. • This increases the blood flow for more work and doesn’t demand more from the heart. • The more you use your muscles the more they increase. Basically the muscles rip and repair.

15. Atrophy: the loss of muscle due to the lack of use. • Astronauts get this.

16. Exercise • Aerobic Exercise: increases the size and strength of your skeletal muscles, but mostly strengthens the heart while increasing the endurance of your skeletal muscles. Ex: jogging, cycling, swimming. • Resistance Exercise: Most effective in increasing size and strength of your skeletal muscles. Resistance require muscles to overcome the weight of another object. Ex: sit-ups, push-ups, lifting.

17. Muscle Injuries: • Muscle strain: pulled muscle, is the overstretching or even tearing of muscle fiber. • Tendon damage: tendinitis is an inflamed tendon.

18. Steroids (anabolic) • Is a synthetic hormone. • They promote tissue growth

19. Facts: • There are more than 650 muscles in the human body. • 40 percent of your body weight is muscle • Eye muscle is the busiest • You largest is usually your gluteus maximus

23. Muscles you need to know: Top portion Trapezius Deltoid Pectoralis Major Triceps Brachii Biceps Brachii Latissimus dorsi Mid External oblique Internal oblique Transversus abdominis Rectus abdominis Bottom General terms Hamstring muscles Quadricep muscles Satorius Rectus femoris Gluteus maximus Quadratus femoris Gastrocnemius Soleus Achillies tendon

30. Get Body Smart

35. Muscle Tutorial

36. The Cat

37. Questions • List three types of muscle tissue, and describe their functions in the body. • Compare aerobic exercise with resistance exercise, and give two examples of each. • Describe the muscle action required to pick up a book. Make a sketch that illustrates the muscle action.