Question

What is a tissue?

Answer 1

Hint Tissue is a collection of cells with similar structures that work together as a unit. The intercellular matrix, a nonliving substance, fills the spaces between the cells. This could be plentiful in some tissues while being scarce in others.

Complete answer:
Tissue is a biological organisational level in biology that exists between cells and an entire organ. A tissue is a collection of cells and extracellular matrix from the same origin that work together to perform a defined function. Multiple tissues are then functionally grouped together to form organs.
Tissues are not present in unicellular organisms by definition. Tissues are absent or poorly differentiated even in the simplest multicellular animals, such as sponges. However, more evolved multicellular animals and plants have specialised tissues that may organise and govern an organism's reaction to its surroundings.
Plants:
Bryophytes (liverworts, hornworts, and mosses) are nonvascular plants that lack true leaves, stalks, and roots as well as vascular tissues (phloem and xylem). Bryophytes, on the other hand, absorb water and nutrients directly through their leaflike and stemlike structures, as well as the cells that make up the gametophyte body.
Animals:
Tissues became aggregated into organs early in the evolutionary history of animals, which were then separated into specialised components.

Note: Histology, or histopathology in the case of disease, is the study of human and animal tissues. Tissues in plants are investigated in both anatomy and physiology. The paraffin block, in which tissue is embedded and later sectioned, the histology dye, and the optical microscope are all traditional techniques for analysing tissues.