You Observe the Structure and Function of a Muscle Fiber

question 22

Multiple Choice

You observe the structure and function of a muscle fiber in the lab. You find that membrane depolarization is not always necessary in order to cause contraction, and that actin filaments are not arranged longitudinally along the length of the fiber. Most likely you are observing a _______________________.

• A) skeletal muscle cell
• B) cardiac muscle cell
• C) smooth muscle cell
• D) skin cell

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Definitions:

Pleura

A thin membrane that surrounds the lungs and lines the interior wall of the chest cavity, providing lubrication and facilitating breathing.

Posterior/Dorsal

Referring to the back side of the body or an organ, opposite of anterior/ventral, important in anatomical positioning.

Popliteal

Pertaining to the area behind the knee where ligaments, vessels, and muscles are located.

Pleural Body Cavity

A fluid-filled space that surrounds the lungs, allowing them to expand and contract without friction, part of the thoracic cavity.