Eukaryotic cells

Eukaryotic Cells

A Eukaryotic cell is a type of cell that contains a nucleus and other organelles enclosed within membranes. Eukaryotes are organisms whose cells have a nucleus enclosed within membranes, unlike Prokaryotes, which are unicellular organisms that do not contain a nucleus. The defining membrane-bound structure that sets eukaryotic cells apart from prokaryotic cells is the nucleus, or nuclear envelope, within which the genetic material is carried.

Characteristics

The key characteristic of a eukaryotic cell is the presence of a nucleus, a membrane-bound structure that contains the cell's genetic material. This nucleus gives the eukaryotic cell its name, which comes from the Greek 'eu' and 'karyon', meaning 'true' and 'kernel' respectively.

In addition to the nucleus, eukaryotic cells contain a variety of other organelles, including mitochondria, the endoplasmic reticulum, the Golgi apparatus, and lysosomes. Each of these organelles performs a specific function necessary for the cell to function properly.

Classification

Eukaryotic cells can be classified into two main types: animal cells and plant cells. Animal cells do not have a cell wall or chloroplasts but they do have a defined nucleus. In contrast, plant cells have a cell wall and chloroplasts but have a less defined nucleus.

Function

The function of a eukaryotic cell is to regulate the various tasks in the cell and to carry genetic material. They are responsible for the synthesis of proteins and the metabolism of lipids.

Evolution

The evolution of eukaryotic cells is thought to have occurred around 1.6–2.1 billion years ago. This is based on the age of the oldest known eukaryotic fossils, the acritarchs, and the age of the Bangiomorpha, the oldest known red algae.

See also

• Cell biology
• Cell nucleus
• Organelle
• Prokaryote