Diversity

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prokaryote:

Size of cell: typically 0.2-2.0 um in diameter

Nucleus: no nuclear membrane or nucleoli

Membrane-enclosed organelles: absent

Flagella: consist of two protein building blocks

Glycocalyx: present as a capsule or slime layer

Cell wall: usually present; chemically complex (typical bacterial cell wall includes peptidoglycan)

Plasma membrane: no carbohydrates and generally lacks sterols

Cytoplasm: no cytoskeleton or cytoplasmic streaming

Ribosomes: smaller size (70S)

Chromosome (DNA): single circular chromosome; lacks histones

Cell division: binary fission

Sexual reproduction: no meiosis ; transfer of DNA fragments

eukaryote:

Size of cell: typically 10-100 um in diameter

Nucleus: true nucleus, consisting of nuclear membrane and nucleoli

Membrane-enclosed organelles: present; examples include lysosomes, golgi complex, endoplasmic reticulum, mitochondria, and chloroplasts

Flagella: complex; consist of multiple microtubules

Glycocalyx: present in some cells that lack a cell wall

Cell wall: when present, chemically simple

Plasma membrane: sterols and carbohydrates that serve as receptors present

Cytoplasm: cytoskeleton; cytoplasmic streaming

Ribosomes: larger size (80S); smaller size (70S) in organelles

Chromosome (DNA): multiple linear chromosomes with histones arrangement

Cell division: mitosis

Sexual reproduction: involves meiosis

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