Which of the following tissues is known for having long cells with high amounts of contractile proteins?

Muscle tissue is specifically designed for contraction and movement, which is why it contains long, elongated cells filled with a high concentration of contractile proteins, such as actin and myosin. These proteins interact within the muscle fibers to produce force and enable movement, whether voluntary or involuntary.

Muscle tissue is divided into different types—skeletal, cardiac, and smooth—each of which has unique structural features and functions. Skeletal muscle is characterized by its striations and is responsible for voluntary movements. Cardiac muscle is found in the heart and operates involuntarily, while smooth muscle lines various internal organs and also functions involuntarily.

In contrast, epithelial tissue functions primarily for protection, secretion, and absorption, featuring tightly packed cells that often lack the specialized structures necessary for contraction. Nervous tissue, composed of neurons and glial cells, is involved in the transmission of signals in the body but does not perform contraction. Connective tissue serves various purposes, including support and binding other tissues together, but it does not comprise the long, contractile cell structures characteristic of muscle tissue. Thus, the defining features of muscle tissue make it the correct choice in this scenario.