Define: Cell, Tissue, Protoplasm

Hint: Cells are the basic structural and functional unit of life. Tissues are formed when a group of similar cells associates together to perform a specific function. Protoplasm is explained as the combination of both cytoplasm and nucleus present in the cell.

Complete answer:
i. A cell is the basic structural and biological unit of all organisms. It is the smallest unit of life. The cells are also referred to as the building blocks of life as they form the main component of organisms. The basic structure of cells consists of cytoplasm which is covered by a plasma membrane, nucleus, and many cell organelles which play a major role in the functioning of the cell. Depending on the number of cells animals can be classified as unicellular i.e. single-celled organisms or multicellular organisms.
ii. The tissue is a cellular organizational level between cells and which combine and form a complete organ and perform a specific function. A tissue is a group of similar cells and their extracellular matrix from the same origin that together carry out a specific function.
iii. The protoplasm is a part of a cell that is covered with a plasma membrane. The plasma membrane along with the nucleus is referred to as protoplasm. It also includes the nucleoplasm. Life is an action of a basic particle, the cell can be compared with the opinion that it is the expression of a living composite substance called protoplasm.

Note: Cells are classified as eukaryotes and prokaryotes based on the presence and absence of a nucleus. In eukaryotic organisms, the nucleus is present with a distinct plasma membrane, on the other hand, in prokaryotes the nucleus is absent. Organs are then formed by the functional grouping together of multiple tissues.