1. Membrane-bound nucleus: This is the defining characteristic of eukaryotes, containing the cell's genetic material (DNA) organized into chromosomes.
2. Membrane-bound organelles: Eukaryotic cells have various specialized compartments within their cytoplasm, each with specific functions. Examples include:
* Mitochondria: Powerhouse of the cell, responsible for ATP production.
* Endoplasmic reticulum (ER): Network of interconnected membranes involved in protein synthesis and lipid metabolism.
* Golgi apparatus: Processes and packages proteins and lipids for secretion or delivery to other organelles.
* Lysosomes: Digest cellular waste and debris.
* Vacuoles: Storage compartments for water, nutrients, and waste products.
* Chloroplasts (in plants and algae): Site of photosynthesis, converting light energy into chemical energy.
3. Cytoskeleton: Network of protein fibers that provides structural support, facilitates movement, and allows for intracellular transport.
4. Ribosomes: Responsible for protein synthesis, found in both the cytoplasm and on the ER.
5. Plasma membrane: Outermost layer of the cell, controlling the movement of substances in and out of the cell.
6. Complex cell wall (in plants, fungi, and some protists): Provides structural support and protection.
7. Sexual reproduction: Although not all eukaryotic organisms reproduce sexually, most do, involving the fusion of gametes (sex cells) to create offspring.
These features distinguish eukaryotes from prokaryotes (bacteria and archaea), which lack a nucleus and other membrane-bound organelles.
