LE 7-2 Hydrophilic head Hydrophobic tail WATER

LE 7-3 Hydrophilic region of protein Hydrophobic region of protein Phospholipid bilayer

LE 7-5b Viscous Fluid Unsaturated hydrocarbon tails with kinks Membrane fluidity Saturated hydro- carbon tails

LE 7-5c Cholesterol Cholesterol within the animal cell membrane

LE 7-8 EXTRACELLULAR SIDE N-terminus C-terminus CYTOPLASMIC SIDE  Helix

LE 7-15a EXTRACELLULAR FLUID Channel protein Solute CYTOPLASM

LE 7-17a Diffusion Facilitated diffusion Passive transport

LE 7-17b ATP Active transport

LE 7-17 Diffusion Facilitated diffusion Passive transport ATP Active transport

LE 6-9a Flagellum Centrosome CYTOSKELETON Microfilaments Intermediate filaments Microtubules Peroxisome Microvilli ENDOPLASMIC RETICULUM (ER Rough ER Smooth ER Mitochondrion Lysosome Golgi apparatus Ribosomes: Plasma membrane Nuclear envelope NUCLEUS In animal cells but not plant cells: Lysosomes Centrioles Flagella (in some plant sperm) Nucleolus Chromatin

LE 6-9b Rough endoplasmic reticulum In plant cells but not animal cells: Chloroplasts Central vacuole and tonoplast Cell wall Plasmodesmata Smooth endoplasmic reticulum Ribosomes (small brown dots) Central vacuole Microfilaments Intermediate filaments Microtubules CYTOSKELETON Chloroplast Plasmodesmata Wall of adjacent cell Cell wall Nuclear envelope Nucleolus Chromatin NUCLEUS Centrosome Golgi apparatus Mitochondrion Peroxisome Plasma membrane

LE 6-10 Close-up of nuclear envelope Nucleus Nucleolus Chromatin Nuclear envelope: Inner membrane Outer membrane Nuclear pore Pore complex Ribosome Pore complexes (TEM)Nuclear lamina (TEM) 1 µm Rough ER Nucleus 1 µm 0.25 µm Surface of nuclear envelope

LE 6-12 Ribosomes Smooth ER Rough ER ER lumen Cisternae Transport vesicle Smooth ER Rough ER Transitional ER 200 nm Nuclear envelope

LE 6-2 Measurements 1 centimeter (cm) = 10 –2 meter (m) = 0.4 inch 1 millimeter (mm) = 10 –3 m 1 micrometer (µm) = 10 –3 mm = 10 –6 m 1 nanometer (nm) = 10 –3 µm = 10 –9 m 10 m 1 m Human height Length of some nerve and muscle cells Chicken egg 0.1 m 1 cm Frog egg 1 mm 100 µm Most plant and animal cells 10 µm Nucleus 1 µm Most bacteria Mitochondrion Smallest bacteria Viruses 100 nm 10 nm Ribosomes Proteins Lipids 1 nm Small molecules Atoms 0.1 nm Unaided eye Light microscope Electron microscope

LE 6-3a Brightfield (unstained specimen) 50 µm Brightfield (stained specimen) Phase-contrast

LE 6-6 A typical rod-shaped bacterium A thin section through the bacterium Bacillus coagulans (TEM) 0.5 µm Pili Nucleoid Ribosomes Plasma membrane Cell wall Capsule Flagella Bacterial chromosome

LE 6-7 Total surface area (height x width x number of sides x number of boxes) Total volume (height x width x length X number of boxes) Surface-to-volume ratio (surface area  volume) Surface area increases while Total volume remains constant

LE 6-11 Ribosomes 0.5 µm ER Cytosol Endoplasmic reticulum (ER) Free ribosomes Bound ribosomes Large subunit Small subunit Diagram of a ribosome TEM showing ER and ribosomes

LE 6-14a Phagocytosis: lysosome digesting food 1 µm Plasma membrane Food vacuole Lysosome Nucleus Digestive enzymes Digestion Lysosome Lysosome contains active hydrolytic enzymes Food vacuole fuses with lysosome Hydrolytic enzymes digest food particles

LE 6-14b Autophagy: lysosome breaking down damaged organelle 1 µm Vesicle containing damaged mitochondrion Mitochondrion fragment Lysosome containing two damaged organelles Digestion Lysosome Lysosome fuses with vesicle containing damaged organelle Peroxisome fragment Hydrolytic enzymes digest organelle components

LE µm Central vacuole Cytosol Tonoplast Central vacuole Nucleus Cell wall Chloroplast

LE Nuclear envelope Nucleus Rough ER Smooth ER

LE Nuclear envelope Nucleus Rough ER Smooth ER Transport vesicle cis Golgi trans Golgi Plasma membrane

LE 6-17 Mitochondrion Intermembrane space Outer membrane Inner membrane Cristae Matrix 100 nm Mitochondrial DNA Free ribosomes in the mitochondrial matrix

LE 6-18 Chloroplast DNA Ribosomes Stroma Inner and outer membranes Granum Thylakoid 1 µm