rial and is usually a single circular molecule of DNA. Karyo-is Greek for “ker-
nel.” A prokaryotic organism, such as a bacterium, is a cell that lacks a mem-
brane-bound nucleus or membrane-bound organelles. The exterior of the cell
usually has glycocalyx, flagellum, fimbriae, and pili (Fig. 4-1).
CHAPTER 4 Prokaryotic and Eukaryotic Cells^69
Characteristics Prokaryotic Cells Eukaryotic Cells
Cell wall Include peptidoglycan Chemically simple
Chemically complex
Plasma membrane No carbohydrates Contain carbohydrates
No sterols Contain sterols
Glycocalyx Contain a capsule or Contained in cells that
a slime layer lack a cell wall
Flagella Protein building blocks Multiple microtubules
Cytoplasm No cytoplasmic streaming Contain cytoskeleton
Contain cytoplasmic streaming
Membrane-bound None Endoplasmic reticulum
organelles Golgi complex
Lysomes
Mitochondria
Chloroplasts
Ribosomes 70S 80S
Ribosomes located in
Organelles are 70S
Nucleus No nuclear membrane Have a nucleus
No nucleoli Have a nuclear membrane
0.2–2.0 mm in diameter Have a nucleoli
10–100 mm in diameter
Chromosomes Single circular chromosome Multiple linear chromosomes
No histones Have histones
Cell division Binary fission Mitosis
Sexual reproductions No meiosis Meiosis
DNA transferred in fragmentsTable 4-2. Differences between Prokaryotic and Eukaryotic Cells