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

   Return to Lecture

   Return to Lecture List