Plastics Are Often Classified into Two Categories

question 9

Multiple Choice

Plastics are often classified into two categories:

• A) foams and vinyls
• B) thermoplastics and thermosets
• C) flexible and rigid
• D) transparent and opaque

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Definitions:

Myofibril

Specific muscle cell organelle containing a linear arrangement of sarcomeres, which shorten to produce muscle contraction.

Sarcomeres

The basic contractile unit of muscle fiber, consisting of actin and myosin filaments between two Z-lines.

Myofilaments

Protein filaments consisting of actin and myosin that are the primary components of muscle contraction.

Acetylcholine

A neurotransmitter in both the central and peripheral nervous systems that plays key roles in arousal, attention, memory, and muscle activation.