Psyc 552 Ergonomics & BiomechanicsLecture 4

Ligaments, Tendons, & Facia Ligament:

Dense connective tissue that connects bone to bone.

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Flexor Retinaculum1 scaphoid 2 trapezium 3 pisiform 4 hamate

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Tendons Tendons

Attach muscles to bones Are surrounded by a sheath called a synovium Synovial fluid facilitates gliding

Fascia Dense connective tissue that covers organs or

parts of organs and separates them from each other.

Collagen fibers Collagen fibers form

both ligaments and tendons.

In tendons, the fibers run parallel to one another

In ligaments, the fibers are not parallel

Muscles 3 types of muscles in the body

Striated Cardiac Smooth

Muscles consist of Muscle cells 3 types of connective tissue… Nerve fibers

Muscle Connective Tissue

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Muscle Fibers Long multinuclear cylindrical cells composed

of parallel myofibrils

Myofibrils Composed of 2 sub units called myofilaments

Myosin Actin

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Muscle Contractile Unit Sacromere

The part of a cross-striated muscle fiber between the z-lines

Nervous Tissue

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Nervous Tissue (cont) Two branches

Sensory Motor

Nerves connect to muscles via the neuromuscular junction

Nerve + muscle fiber = motor unit

Muscular Contraction

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Muscle Contraction (cont)

Energy for Muscles Adenosine triphosphate ATP

Anaerobic metabolism

Aerobic metabolism