cells, as in the amoeboid migration of tissue macrophages; the beating encloses the cytoplasm. All cells, except mature red blood cells, also
of flagella or cilia to move the cell (e.g. in spermatozoa) or fluids overly- contain a nucleus that is surrounded by a nuclear membrane or enve-
ing it (e.g. in respiratory epithelium); cell division; and muscle contrac- lope (see Fig. 1.1; Fig. 1.2). The nucleus includes: the genome of the
tion. Cell movements are also involved in the uptake of materials from cell contained within the chromosomes; the nucleolus; and other sub-
their environment (endocytosis, phagocytosis) and the passage of large nuclear structures. The cytoplasm contains cytomembranes and several
molecular complexes out of cells (exocytosis, secretion). membrane-bound structures, called organelles, which form separate
Surface projections
(cilia, microvilli)
Surface invagination
Actin filaments
Vesicle Mitochondrion
Cell junctions
Plasma membrane
Desmosome Peroxisomes
Cytosol
Nuclear pore
Intermediate