Why is the cell called the structural and functional unit of life

Answer:

A cell is the basic unit of life. It is the smallest structure capable of independent survival and reproduction. The properties of cells are determined by their unique structures and functions. It is a complex, self-contained unit composed of many different types of molecules that work together to perform all the functions necessary for survival.

All cells are made up of one or more membranes that surround the central nucleus and cytoplasm. The cytoplasm contains many different organelles such as ribosomes, mitochondria and chloroplasts, which perform specific functions within the cell.

Cells are very small. For example, the average size of a human red blood cell is 7 microns (0.0025 mm). The size of a cell varies from species to species and from one type of cell to another. For example, plant cells are larger than animal cells because they contain more water and other substances that don’t fit into animal cells.

Cells are too small to be seen with the naked eye. Cells are huge compared to other structures like organs or tissues. Cells are so complex that they can make their own food through photosynthesis or respiration. The cell is also important because it makes up everything in our bodies, including skin, muscle, bone cartilage and even blood cells.

The most common type of cell in living things is called eukaryotic. Eukaryotes are organisms whose cells contain membrane-bound organelles such as mitochondria and chloroplasts (which make food for themselves). These organelles can be found in prokaryotes as well, but they are not enclosed in membranes like they are in eukaryotes.

Cells also have a nucleus that contains DNA which carries genetic information. The nucleus also contains many proteins that help with gene expression and replication which occurs during mitosis or meiosis.