The group of cells that perform a particular function are called tissue.The following are some facts about tissue:

There are four types of tissue in human beings: epithelial, connective, muscle, and nervous tissue:

a. Epithelial Tissue: These are closely packed cells ideal for forming a lining or a covering, It is what makes up the skin. This tissue also makes up the lining for the organs and the passageways in the body. It allows the skin to be an excellent barrier and protects the body against injury and invading microorganisms (any form of life that is too small to be seen without a microscope).

b. Nervous Tissue: The nervous tissues are made of cells called neurons. These are designed to carry nerve impulses. This highly specialized tissue carries electrical signals from one part of the body to another.

c. Muscle Tissue: Muscle tissue is responsible for producing body movement. Its cells are designed to work by contracting and relaxing as required. They also are built to respond to the stimuli transmitted by neurons.

d. Connective Tissue: Connective tissue is the most common tissue in the body because it holds the entire body together. Bone, cartilage, and blood are made of connective tissues. Bone is a type of mineralized connective tissue, cartilage is found between joints, and the blood is considered to be a connective tissue in liquid form since it circulates throughout the body.

So, the correct answer is, ‘Tissue.’

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