• The muscles are responsible for all movement of the body
  HOW does it create movement?
  -by flexing and extending

• The three basic types of muscles :

  1. Skeletal

  2. Cardiac

  3. Smooth

• Muscles are body energy converters and contain many mitochondria since they have a high energy demand

  • How much percent of the body weight is muscle?

    • 50% of body weight is muscle

• What is a muscle made up of?

  • water and proteins

Tendons and Ligaments

• Tendons- a tough band of fibrous connective tissue that usually

  connects muscle to bones

  • capable of withstanding tension

• Ligaments-the fibrous connective tissue that connects bone to other bone

  • keeps structure stable

Characteristics of Muscles

• Skeletal and Smooth are…

  • elongated

• What is a Muscle Cell?

  • Muscle FIBER

• What causes Muscle Contraction?

  • the movement of microfilaments (protein fibres)

Skeletal Muscle

• Multinucleated-

  • have more than one nucleus

• Why are they multinucleated ?

  • they’re formed from the fusion of multiple cells

  • to ensure the muscle fiber produces enough proteins to meet the high energy demands

• What do the skeletal muscles contain?

  • Many kinds of mitochondria → produce energy in the form of ATP

• Skeletal muscle is striated = striped, banding

• What type of Muscle is consciously controlled?

  • Skeletal Muscle (Voluntary)

  • telling body what to do

• Four functions of the skeletal muscle:

  1. Produce movement

  2. Maintain posture

  3. Generate heat

  4. Stabilize joints

• What is the shape of a cell (fibre) of a skeletal muscle?

  • long and cylindrical

    

-Typically 50-60mm, and up to 10 cm long

• What are Myofibrils?

  • units in the muscle that can contract and shorten

Muscle Contraction

• What do the Myofibrils contain?

  • They contain 2 protein filaments

    1. Actin

    2. Myosin

  • What do these filaments do?

    • they overlap and use energy from mitochondria called ATP

  • What does the ATP do in the filaments? (MUSCLE MOVER)

    • ATP powers filaments to slide over each other to shorten the myofibril (causes Muscle contraction)

• What is Sliding Filament Theory

  • The explanation of how muscles contract

Smooth Muscle