Cell

Cell is a structural and functional unit of living organism, Because it forms body structure and perform the physilological process in life.

It is called building block of life. How a unit bricks rearranges one after another and construct a big building, as same as that cell rearranges one after another and forms tissues, multiple tissues forms organ, multiple organ forms system and multiple system forms the body. 

It is called functional unit because it performs the physilological process of life. Just for example,

Metabolism: Producing energy by mitochondria

Conversion of glucose into energy inside cell.

Growth: After birth transformation from smaller size to bigger size is called growth. How amazing we became younger from baby? How amazing after certain period of germination a seedlings turned into tree. Even matured for fruiting. This is the magic of growth caused by mitosis cell division.

Reproduction: In reproduction cell have an active role. Egg cell and sperm cell forms zygote. 

Inheritance career: The property of ancestors are inheritance. In biology, characteristics and properties of ancestors flowing to offspring is called inheritance. DNA in Nucleus is career of inheritance. 

Protein synthesis: Ribosome have active role in protein synthesis. Ribosome synthesize protein and transport it to endoplasmic reticulum. Endoplasmic reticulum gives proteins shape and transport to golgi apparatus. Golgi apparatus packed it and transport inside and outside of the cell. 

Lysosome involves in phagocytosis, it is nothing but engulfing of waste materials. We heard about greatest discovery, greatest power of fasting for certain period of time that cell can engulf cancer gene or any toxic materials by phagocytosis. 

Lysosome also involves in apoptosis that is engulfing of death cell by any cell.

Cell membrane enclosed all of the organalae and cytoplasm and nucleus.

 everything inside cell membrane is protoplasm. Everything inside cell membrane, except nucleus is called cytoplasm. 

Cytoplasm is semi liquid and contains other organalae of cell.