prokarionták

Prokaryotes are single-celled organisms that lack a membrane-bound nucleus and other membrane-bound organelles. Their genetic material, typically a single circular chromosome, is located in a region of the cytoplasm called the nucleoid. Prokaryotic cells are generally much smaller than eukaryotic cells, with dimensions ranging from 0.1 to 5.0 micrometers in diameter.

The two major domains of prokaryotes are Bacteria and Archaea. Bacteria are ubiquitous and found in diverse environments, playing crucial roles in ecosystems, such as nutrient cycling and decomposition. They have a cell wall, usually made of peptidoglycan, which provides structural support and protection.

Archaea, on the other hand, are often found in extreme environments like hot springs, salt lakes, and deep-sea hydrothermal vents, although some are also found in more common habitats. Many archaea have unique metabolic pathways and cell wall compositions that differ from bacteria. They were initially thought to be bacteria but are now recognized as a distinct domain of life.

Reproduction in prokaryotes is primarily asexual, occurring through binary fission, where a single cell divides into two identical daughter cells. Some prokaryotes can also exchange genetic material through processes like conjugation, transformation, and transduction, which contribute to genetic diversity. Despite their structural simplicity, prokaryotes exhibit remarkable metabolic diversity, utilizing a wide range of energy and carbon sources.