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Cytology

Table 1.1: Differences between prokaryotic and eukaryotic cells

Criteria/ Feature Prokaryotic cells Eukaryotic cells

Cell type Mainly unicellular (in Mainly multicellular (except to
some cyanobacteria may members of kingdom Protoctista,
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be multicellular) which are mainly unicellular
organisms)
Nucleus Have no true nucleus Have a true nucleus, bound by a
double membrane

Double membrane Have no double Have many double membrane bound
bound organelles membrane bound organelles, such as mitochondria,
organelles chloroplasts, and nucleus

DNA Have circular DNA Have helical or linear DNA

Have naked DNA Have DNA associated with proteins
known as histones and is organised
into chromosomes

Ribosomes Have small and Have larger and more complex
simple ribosomes (70s ribosomes (80s ribosomes)
ribosomes)
Cytoplasm Have only one type of Filled with a large and complex
organelles, that is, the collection of organelles, many
ribosomes of them enclosed in their own
membranes

Cell size Small in size Relatively large in size
Functional Have only one membrane Have many different functional
compartments (the plasma membrane) compartments separated by
enclosing all of the cell’s membranes
internal contents

Cell wall Mureinic cell wall Cellulose or chitinous cell wall

Cilia and flagella Do not arise from basal Arise from basal bodies and have 9+2
bodies and lack micro- arrangement of microtubules
tubules

Cell division Involves binary fission or Involves mitosis, meiosis or both
budding

Reproduction No meiosis. Transfer Involves meiosis during gamete
of DNA is done by formation
conjugation only

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