A fascicle is a a. muscle, b. bundle of muscle fibers enclosed by a connective tissue sheath, c. bundle of myofibrils, d. group of myofilaments.

Verified step by step guidance

1. Step 1: Understand the structure of a muscle. Muscles are composed of multiple layers of organization, starting from the smallest unit to the largest.
2. Step 2: Recognize that myofilaments are the smallest structural units, which group together to form myofibrils.
3. Step 3: Know that myofibrils are organized into muscle fibers (muscle cells), which are the basic cellular units of a muscle.
4. Step 4: Learn that a fascicle is a bundle of these muscle fibers, and it is surrounded by a connective tissue sheath called the perimysium.
5. Step 5: Conclude that the correct answer is the option that describes a fascicle as a bundle of muscle fibers enclosed by a connective tissue sheath.

Key Concepts

Fascicle

A fascicle is a structural unit within skeletal muscle, consisting of a bundle of muscle fibers (myofibers) that are grouped together and surrounded by a connective tissue sheath called the perimysium. This organization allows for efficient force generation and coordination during muscle contraction.

Muscle Fibers

Muscle fibers, or myofibers, are the individual cells that make up skeletal muscle. They are long, cylindrical cells that contain multiple nuclei and are responsible for muscle contraction. Each muscle fiber is composed of myofibrils, which are further made up of myofilaments, the proteins that facilitate contraction.

Connective Tissue Sheath

The connective tissue sheath surrounding a fascicle is known as the perimysium. This layer not only provides structural support and protection to the muscle fibers but also contains blood vessels and nerves that supply the muscle, playing a crucial role in muscle function and health.