Eukaryotes And Prokaryotes - SS1 Biology Lesson Note
The primary difference between prokaryotes and eukaryotes lies in the complexity of their cellular structure and organization.
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Here are the key distinctions:
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Cell Structure: Prokaryotes are single-celled organisms that lack a true nucleus and membrane-bound organelles. Their genetic material, a circular DNA molecule, is found in the cytoplasm. Eukaryotes, on the other hand, can be single-celled or multicellular and have a true nucleus that houses their DNA.
Nucleus: Prokaryotes do not have a distinct nucleus. Their genetic material is free-floating in the cytoplasm, forming a region called the nucleoid. In contrast, eukaryotes have a membrane-bound nucleus that encloses their DNA, separating it from the cytoplasm.
Organelles: Prokaryotes lack membrane-bound organelles, except for some internal membrane structures like mesosomes in some bacteria. Eukaryotes have a more elaborate internal organization with various membrane-bound organelles, including mitochondria for energy production, endoplasmic reticulum for protein synthesis, and Golgi apparatus for processing and packaging molecules.
Size and Complexity: Prokaryotes are typically smaller and less complex than eukaryotes. Eukaryotic cells are generally larger and exhibit greater structural complexity due to the presence of membrane-bound organelles.
Reproduction: Prokaryotes reproduce asexually through binary fission, where a single cell divides into two identical daughter cells. Some prokaryotes can also exchange genetic material through horizontal gene transfer. Eukaryotes reproduce through various methods, including asexual reproduction (e.g., mitosis) and sexual reproduction (e.g., meiosis and fertilization).
Diversity: Prokaryotes include bacteria and archaea, which are both groups of single-celled organisms with distinct genetic and biochemical characteristics. Eukaryotes encompass a broader range of organisms, including plants, animals, fungi, and protists. Eukaryotes exhibit greater morphological, physiological, and ecological diversity.
These differences in cellular structure and organization contribute to various functional disparities between prokaryotes and eukaryotes, such as differences in metabolism, ability to specialize in specific functions, and adaptability to different environments. Understanding these distinctions is crucial for studying the diversity of life and the fundamental processes that govern living organisms.