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Cell

The cell is the smallest structural and functional unit in living organisms. It is the basis of all vital functions. It is the basic building unit. Some organisms may consist of only one cell. Many organisms are made up of billions of cells. All cells are based on a similar basic plan, Similar mechanisms are used to synthesize proteins and convert energy to transport their essentials. Although the cells of the body are similar, they have amazing properties that distinguish them from each other easily. Each cell is remarkably independent. Each cell receives a supply of nutrients and oxygen from the blood , And m Cell components and their vital parts, with a specific task in which the cell's life is maintained.

Cell components

Despite the apparent variation of cell types, cell components do not differ by cell type, and cell components are as follows:

Plasma membrane: The thin wall that line the cell from the outside. This membrane plays an important role in isolating the cell from its surrounding environment.

The nucleus: serves as the center of the cell's command, to grow the cell and mature and divide, it also contains DNA, the genetic material of the cell, surrounds the nucleus of a membrane called the nuclear casing, protects the DNA and separates the nucleus from the rest of the cell.

Cytoplasm: It is found inside the cells and consists of a gel-like liquid called the cellular cytoskeleton, in addition to the structures surrounding the nucleus.

The endoplasmic network: These cells help to process molecules that are created by the cell. These molecules move to their specific targets, either inside or outside the cell.

Ribosomes are organelles that process the cell's genetic instructions to create proteins.

Cytoskeleton: is the outer frame of the cell, which performs a lot of functions.

Golgi device: Molecules are processed by the endoplasmic network, to be transferred outside the cell.

Particles: These organelles, the recycling center of the cell, digest bacteria that invade the cell, rid the cell of toxic substances, and recycle the components of worn cells.

Mitochondria are complex organelles that transform energy from food into a form that the cell can use.

Cell theory

Many biologists have agreed on a common theory, called cell theory, which states:

All living organisms consist of one or more cells.

All cells carry out life activities, require energy and growth and have a specific size.

New cells of other living cells are created, through the process of cellular division.

The cell has specialized structures called organelles, which perform certain functions within the cell.

All cells have the same chemical composition.

Total cell activity determines the activity of the organism.

The most famous cell scientists

Galileo's world: which had an important role in the discovery of the cell, where he made a microscope, which was the real nucleus, to detect the cell.

Robert Hooke: The name of the cell, after being seen through a microscope, was launched in 1665

Robert Brown: The kernel and some cell components.

Matthias Schleiden: The theory of cell.