Digital Identity is Under Attack: FIDO Paris Seminar.pptx
Cells
1. Cells
The cell is the basic structural and functional unit of all known living organisms. It is
the smallest unit of life that is classified as a living thing. Some organisms, such as most
bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are
multi-celled
Robert Hocke discovered the cell when he was watching the cork in the microscopy.
There are two types of cells: eukaryotic and prokaryotic. Prokaryotic cells are usually
independent, while eukaryotic cells are often found in complex organisms. In all cells
we can differentiate three parts: the cell membrane, the cytoplasm and the genetic
material.
Prokaryotic cells
The prokaryotic cell is simpler, and therefore smaller, than a eukaryote cell. The genetic
material is dispersed in the cytoplasm. Bacteria are typical prokaryotic cells.
A prokaryotic cell has:
•On the outside, flagella and pili project from the cell's surface. These are structures
that (not present in all prokaryotes) facilitate movement and communication
between cells.
•Inside the cell is the cytoplasm that contains the cell genome (DNA), ribosome and
other structures.
•The cell wall is another typical structure of prokaryotic cell.