1. 14.3 Muscular system
Key concepts: what types of muscles are found in the body? Why do skeletal muscles work in pairs?
Key terms: involuntary muscle, voluntary muscle, skeletal muscle, tendon, striated muscle, smooth muscle, cardiac muscle

2. Types of muscle Involuntary – not under conscious control
Voluntary – under your conscious control
Three types of tissue – skeletal muscle tissue, smooth muscle tissue, and cardiac muscle tissue

3. Skeletal
Skeletal muscles are attached to your skeleton and provide the force that moves you around
At the end of each skeletal muscle is a tendon.
A tendon is a strong connective tissue that attaches muscle to bone.
Skeletal muscle cells appear banded, or striated, and is sometimes called striated muscle.

5. Smooth muscle
Smooth muscles are involuntary. They work automatically to control certain movements inside your body, like digestion.
Not striated
React more slowly and tire more slowly

6. Cardiac muscle Found only in your heart. Involuntary Striated
Does not get tired

7. Muscle Tissues

8. Muscles at work
Because muscles cells can only contract, not extend, skeletal muscles must work in pairs. While one contracts, the other muscle relaxes to its original length.

9. Muscles work in pairs Biceps and triceps.
Biceps contract, triceps relax, and vice versa

10. Muscular strength and flexibility
Exercise makes individual cells grow in size. As a result, the whole muscle becomes thicker.
Thicker muscles are stronger. Yay.