Cellular Structure Differences: Prokaryotic vs Eukaryotic

Cellular Structure Differences

• Prokaryotic cells lack a nucleus and other membrane-bound organelles. Eukaryotic cells possess a nucleus and various membrane-bound organelles.
• Prokaryotic cells are generally smaller and simpler in structure than eukaryotic cells.
• The genetic material (DNA) in prokaryotic cells is circular and located in the cytoplasm, a region called the nucleoid. Eukaryotic DNA is linear and contained within the nucleus.

Prokaryotic Cell Structure

• Cell wall: Provides structural support and protection. Composed of peptidoglycan in bacteria, but different in archaea.
• Cell membrane: Regulates the passage of substances into and out of the cell, crucial for homeostasis.
• Cytoplasm: The jelly-like substance filling the cell, containing ribosomes and other essential components.
• Ribosomes: Involved in protein synthesis. Prokaryotic ribosomes are smaller than eukaryotic ribosomes.
• Capsule (some prokaryotes): A protective layer outside the cell wall, aiding in attachment and preventing desiccation.
• Flagella (some prokaryotes): Long, whip-like appendages that aid in movement.
• Pili (some prokaryotes): Hair-like appendages that facilitate attachment to surfaces or other cells.

Eukaryotic Cell Structure

• Nucleus: Contains the cell's genetic material (DNA) and controls cellular functions.
• Endoplasmic Reticulum (ER): A network of membranes involved in protein and lipid synthesis.
• Golgi apparatus: Processes, sorts, and packages proteins and lipids for secretion or use within the cell.
• Mitochondria: The "powerhouses" of the cell, responsible for cellular respiration and ATP production.
• Lysosomes: Contain digestive enzymes to break down waste materials and cellular debris.
• Vacuoles: Storage sacs for water, nutrients, or waste products. Plant cells often have a large central vacuole.
• Cytoskeleton: A network of protein fibers providing structural support, facilitating cell movement, and intracellular transport.

Ribosomes in both types

• Ribosomes are present in both prokaryotic and eukaryotic cells, crucial for protein synthesis.

Key Differences Summarized

Reproduction

• Prokaryotes primarily reproduce asexually through binary fission.
• Eukaryotes reproduce both sexually and asexually.

Metabolic Diversity

• Prokaryotes exhibit remarkable metabolic diversity, playing crucial roles in nutrient cycling and decomposition.
• Eukaryotic metabolisms are more complex, supporting a wide range of functions.

Genetic Recombination in Prokaryotes

• Prokaryotes can exchange genetic material through processes like conjugation, transformation, and transduction. This contributes to genetic diversity.

Domains

• Prokaryotic organisms are classified into two domains: Bacteria and Archaea.
• Eukaryotic organisms are part of the domain Eukarya.

Importance of Prokaryotes

• Prokaryotes are essential for ecosystem function and have various applications in biotechnology.

Differences in Genetic Material Expression

• Control mechanisms for gene expression are more complex in eukaryotes compared to prokaryotes, leading to greater regulation of protein production.