Ch. 7 Diagrams Cell Structure

Figure m 1 m 0.1 m 1 cm 1 mm 100  m 10  m 1  m 100 nm 10 nm 1 nm 0.1 nm Atoms Small molecules Lipids Proteins Ribosomes Viruses Smallest bacteria Mitochondrion Most bacteria Nucleus Most plant and animal cells Human egg Frog egg Chicken egg Length of some nerve and muscle cells Human height Unaided eye Light microscopy Electron microscopy Super- resolution microscopy

Brightfield (unstained specimen) Brightfield (stained specimen) 50  m Confocal Differential-interference- contrast (Nomarski) Fluorescence 10  m Deconvolution Super-resolution Scanning electron microscopy (SEM) Transmission electron microscopy (TEM) Cross section of cilium Longitudinal section of cilium Cilia Electron Microscopy (EM) 1  m 10  m 50  m 2  m Light Microscopy (LM) Phase-contrast Figure 6.3

Differential centrifugation Centrifuged at 1,000 g (1,000 times the force of gravity) for 10 min Supernatant poured into next tube 20 min 60 min Pellet rich in nuclei and cellular debris 3 hr Pellet rich in mitochondria (and chloro- plasts if cells are from a plant) Pellet rich in “microsomes” Pellet rich in ribosomes 20,000 g 80,000 g 150,000 g TECHNIQUE (cont.) Figure 6.4b

Fimbriae Bacterial chromosome A typical rod-shaped bacterium (a) Nucleoid Ribosomes Plasma membrane Cell wall Capsule Flagella A thin section through the bacterium Bacillus coagulans (TEM) (b) 0.5  m Figure 6.5

Figure 6.6 Outside of cell Inside of cell 0.1  m (a) TEM of a plasma membrane Hydrophilic region Hydrophobic region Hydrophilic region Carbohydrate side chains Proteins Phospholipid (b) Structure of the plasma membrane

Surface area increases while total volume remains constant Total surface area [sum of the surface areas (height  width) of all box sides  number of boxes] Total volume [height  width  length  number of boxes] Surface-to-volume (S-to-V) ratio [surface area  volume] Figure 6.7

Figure 6.8a ENDOPLASMIC RETICULUM (ER) Rough ER Smooth ER Nuclear envelope Nucleolus Chromatin Plasma membrane Ribosomes Golgi apparatus Lysosome Mitochondrion Peroxisome Microvilli Microtubules Intermediate filaments Microfilaments Centrosome CYTOSKELETON: Flagellum NUCLEUS

Nuclear envelope Nucleolus Chromatin Golgi apparatus Mitochondrion Peroxisome Plasma membrane Cell wall Wall of adjacent cell Plasmodesmata Chloroplast Microtubules Intermediate filaments Microfilaments CYTOSKELETON Central vacuole Ribosomes Smooth endoplasmic reticulum Rough endoplasmic reticulum Figure 6.8c

Nucleus Rough ER Nucleolus Chromatin Nuclear envelope: Inner membrane Outer membrane Nuclear pore Chromatin Ribosome Pore complex Close-up of nuclear envelope Figure 6.9a

Figure  m Free ribosomes in cytosol Endoplasmic reticulum (ER) Ribosomes bound to ER Large subunit Small subunit Diagram of a ribosome TEM showing ER and ribosomes

Figure 6.11 Smooth ER Rough ER ER lumen Cisternae Ribosomes Smooth ER Transport vesicle Transitional ER Rough ER 200 nm Nuclear envelope

Figure 6.13 Nucleus Lysosome 1  m Digestive enzymes Digestion Food vacuole Lysosome Plasma membrane (a) Phagocytosis Vesicle containing two damaged organelles 1  m Mitochondrion fragment Peroxisome fragment (b) Autophagy Peroxisome Vesicle Mitochondrion Lysosome Digestion

Figure 6.14 Central vacuole Cytosol Nucleus Cell wall Chloroplast Central vacuole 5  m

Nucleus Endoplasmic reticulum Nuclear envelope Ancestor of eukaryotic cells (host cell) Engulfing of oxygen- using nonphotosynthetic prokaryote, which becomes a mitochondrion Mitochondrion Nonphotosynthetic eukaryote Mitochondrion At least one cell Photosynthetic eukaryote Engulfing of photosynthetic prokaryote Chloroplast Figure 6.16

Figure 6.17 Intermembrane space Outer membrane DNA Inner membrane Cristae Matrix Free ribosomes in the mitochondrial matrix (a) Diagram and TEM of mitochondrion (b) Network of mitochondria in a protist cell (LM) 0.1  m Mitochondrial DNA Nuclear DNA Mitochondria 10  m

Figure 6.18a Ribosomes Stroma Inner and outer membranes Granum 1  m Intermembrane space Thylakoid (a) Diagram and TEM of chloroplast DNA

Column of tubulin dimers Tubulin dimer 25 nm   Actin subunit 7 nm Keratin proteins 8  12 nm Fibrous subunit (keratins coiled together) 10  m 5  m Table 6.1

Centrosome Longitudinal section of one centriole Centrioles Microtubule 0.25  m Microtubules Cross section of the other centriole Figure 6.22

Direction of swimming (b) Motion of cilia Direction of organism’s movement Power stroke Recovery stroke (a) Motion of flagella 5  m 15  m Figure 6.23

© 2011 Pearson Education, Inc. Animation: Cilia and Flagella Right-click slide / select “Play”

Microtubules Plasma membrane Basal body Longitudinal section of motile cilium (a) 0.5  m 0.1  m (b) Cross section of motile cilium Outer microtubule doublet Dynein proteins Central microtubule Radial spoke Cross-linking proteins between outer doublets Plasma membrane Triplet (c) Cross section of basal body Figure 6.24

Figure 6.25 Microtubule doublets Dynein protein ATP (a) Effect of unrestrained dynein movement Cross-linking proteins between outer doublets ATP Anchorage in cell (b) Effect of cross-linking proteins (c) Wavelike motion 1 2 3

Figure 6.27 Muscle cell Actin filament Myosin filament head (a) Myosin motors in muscle cell contraction 0.5  m 100  m Cortex (outer cytoplasm): gel with actin network Inner cytoplasm: sol with actin subunits (b) Amoeboid movement Extending pseudopodium 30  m (c) Cytoplasmic streaming in plant cells Chloroplast

Figure 6.30 EXTRACELLULAR FLUID Collagen Fibronectin Plasma membrane Micro- filaments CYTOPLASM Integrins Proteoglycan complex Polysaccharide molecule Carbo- hydrates Core protein Proteoglycan molecule Proteoglycan complex

© 2011 Pearson Education, Inc. Animation: Tight Junctions Right-click slide / select “Play”

© 2011 Pearson Education, Inc. Animation: Desmosomes Right-click slide / select “Play”

© 2011 Pearson Education, Inc. Animation: Gap Junctions Right-click slide / select “Play”

Figure 6.32 Tight junctions prevent fluid from moving across a layer of cells Tight junction TEM 0.5  m TEM 1  m TEM 0.1  m Extracellular matrix Plasma membranes of adjacent cells Space between cells Ions or small molecules Desmosome Intermediate filaments Gap junction

Figure 6.UN01 Nucleus (ER) (Nuclear envelope)