The Smallest Muscle Fiber Bundles Responsible for Muscle Contraction Are

question 50

Multiple Choice

The smallest muscle fiber bundles responsible for muscle contraction are known as:

• A) fasciculi.
• B) myofilaments.
• C) reticulum.
• D) myofibrils.

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Definitions:

Segmentation

A body plan in which the body is divided into a series of compartments (segments).

Deuterostomia

Deuterostomia is a major division of the animal kingdom that includes groups like the chordates and echinoderms, characterized by the developmental feature in which the anus forms from the first opening in the embryo, with the mouth forming later.

Protostomes

A major group of animals in which the mouth develops from the first opening in the embryo, with examples including mollusks, annelids, and arthropods.

Spiral Cleavage

A type of embryonic development in some molluscs and annelids where cells divide in a spiral pattern.