Which of the following is NOT considered a tissue?

The heart is not considered a tissue; rather, it is an organ made up of various types of tissues. The heart primarily consists of cardiac muscle tissue, connective tissue, nervous tissue, and epithelial tissue. Each of these tissues plays a crucial role in the overall function of the heart.

On the other hand, blood is classified as a connective tissue that plays a vital role in transportation and regulation within the body. Muscle tissue refers to the tissue responsible for movement, and nervous tissue is involved in communication within the body by transmitting nerve impulses. Understanding the distinction between organs and tissues is essential in the study of anatomy and physiology, as it highlights the complexity of the body’s organization where tissues combine to form organs, and organs collaborate to create organ systems.