Comparison Between Prokaryotic and Eukaryotic Cells
Characteristic
Prokaryotes
Eukaryotes
Size of cell
Typically 0.2-2.0 m m in diameter
Typically 10-100 m m in diameter
Nucleus
No nuclear membrane or nucleoli (nucleoid)
True nucleus, consisting of nuclear membrane & nucleoli
Membrane-enclosed organelles
Absent
Present; examples include lysosomes, Golgi complex, endoplasmic reticulum, mitochondria & chloroplasts
Flagella
Consist of two protein building blocks
Complex; consist of multiple microtubules
Glycocalyx
Present as a capsule or slime layer
Present in some cells that lack a cell wall
Cell wall
Usually present; chemically complex (typical bacterial cell wall includes peptidoglycan)
When present, chemically simple
Plasma membrane
No carbohydrates and generally lacks sterols
Sterols and carbohydrates that serve as receptors present
Cytoplasm
No cytosketeton or cytoplasmic streaming
Cytoskeleton; cytoplasmic streaming
Ribosomes
Smaller size (70S)
Larger size (80S); smaller size (70S) in organelles
Chromosome (DNA) arrangement
Single circular chromosome; lacks histones
Multiple linear chromosomes with histones
Cell division
Binary fission
Mitosis
Sexual reproduction
No meiosis; transfer of DNA fragments only (conjugation)
Involves meiosis
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