Eukaryotic Organisms

Characteristics of Eukaryotic Organisms

General Properties

  • Eukaryotes are one of the key groups of living organisms that fall under the category of complex forms of life.
  • The term Eukaryotic refers to any organism whose cell(s) have a nucleus and other organelles enclosed within membranes.
  • Organisms such as animals, plants, fungi and protists all fall under the category of eukaryotic organisms.

Cell Complexity

  • Eukaryotic cells are typically much larger than prokaryotic cells.
  • Eukaryotic cells possess many specialized structures, termed organelles, that perform specific functions, such as the nucleus, mitochondria, and chloroplasts.
  • In addition to organelles, eukaryotic cells also include a cytoskeleton for maintaining cell shape and facilitating movement.

DNA Structure

  • Unlike prokaryotes, eukaryotic cells keep their genetic material separated from the rest of the cell by a nuclear envelope, forming a structure called the nucleus.
  • Eukaryotes have linear DNA molecules packed into chromosomes, which are associated with histone proteins, aiding the organisation of DNA within the cell.


  • Eukaryotic organisms reproduce in many ways, including both asexual and sexual reproduction.
  • Some eukaryotic cells (meiotic cells) undergo meiosis to produce haploid sex cells or gametes, which can then combine to create new, genetically unique individuals during sexual reproduction.

Nutrition and Respiration

  • Eukaryotic organisms may be photosynthetic (like most plants), heterotrophic (like animals that ingest nutrients) or saprotrophic (like fungi that absorb nutrients from dead or decaying matter).
  • Eukaryotes carry out respiration in the mitochondria where they make use of oxygen to release energy from glucose, this process is known as aerobic respiration.

Distribution and Diversity

  • Eukaryotic organisms are present in nearly all habitats: they are found in various environments from the deepest oceans to the highest mountains.
  • The kingdom of eukaryotic organisms is extremely diverse and comprises plants, animals, fungi, and various microorganisms like protists. Each group has unique characteristics and contributes to biodiversity on Earth.