10 m
Human height 1 m Length of some nerve and muscle cells Fimbriae 0.1 m Chicken egg Nucleoid
1 cm Unaided eye Ribosomes Frog egg 1 mm Plasma membrane
100 µm Bacterial Cell wall Most plant and chromosome animal cells Capsule 10 µm Nucleus Most bacteria 0.5 µm Mitochondrion microscope Light Flagella 1 µm (a) A typical (b) A thin section rod-shaped through the 100 nm Smallest bacteria bacterium bacterium Viruses Bacillus Ribosomes 10 nm coagulans (TEM) Proteins microscope Electron Lipids 1 nm Small molecules
0.1 nm Atoms 1 2
(a) TEM of a plasma Surface area increases while Outside of cell membrane total volume remains constant
5 Inside of 1 0.1 µm 1 cell Carbohydrate side chain Total surface area [Sum of the surface areas 6 150 750 (height × width) of all boxes Hydrophilic sides × number of boxes] region Total volume [height × width × length × 1 125 125 number of boxes] Hydrophobic region Surface-to-volume Hydrophilic (S-to-V) ratio Phospholipid Proteins 6 1.2 6 region [surface area ÷ volume] (b) Structure of the plasma membrane 3 4
Nuclear envelope Rough endoplasmic Nuclear reticulum envelope NUCLEUS Nucleolus ENDOPLASMIC RETICULUM (ER) Chromatin Nucleolus NUCLEUS Smooth endoplasmic Rough ER Smooth ER reticulum Flagellum Chromatin Ribosomes
Centrosome Plasma membrane Central vacuole Golgi apparatus CYTOSKELETON: Microfilaments Microfilaments Intermediate CYTO- filaments Intermediate SKELETON filaments Microtubules Microtubules Ribosomes Mitochondrion Microvilli Peroxisome Chloroplast Plasma membrane Golgi Peroxisome apparatus Cell wall Plasmodesmata Mitochondrion Wall of adjacent cell Lysosome 5 6 Nucleus
Central vacuole Rough ER
Cytosol Smooth ER cis Golgi
Nucleus Central vacuole
Cell wall Plasma Chloroplast membrane trans Golgi 5 µm 7 8
Intermembrane space Outer membrane
Ribosomes Free Stroma ribosomes Inner and outer in the membranes mitochondrial matrix Inner Granum membrane 1 µm Cristae Thylakoid Matrix
0.1 µm
9 10
Direction of swimming
(a) Motion of flagella 5 µm
Direction of organism’s movement
Power stroke Recovery stroke
(b) Motion of cilia 15 µm 11