4.1 Introduction to the Cell pp. 69-72 What’s inside? Organelles = internal structures that do specific jobs Eukaryotes = cells that have membranes around their organelles Prokaryotes = cells that don’t have membranes around organelles Can you name some eukaryotes? Name some prokaryotes?

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

ENDOPLASMIC RETICULUM (ER) Nucleolus NUCLEUS Rough ER Smooth ER Fig. 6-9a Nuclear envelope ENDOPLASMIC RETICULUM (ER) Nucleolus NUCLEUS Rough ER Smooth ER Flagellum Chromatin Centrosome Plasma membrane CYTOSKELETON: Microfilaments Intermediate filaments Microtubules Ribosomes Microvilli Golgi apparatus Peroxisome Mitochondrion Lysosome

4.1 Introduction to the Cell pp. 69-72 Cell membranes Made of lipid bilayers that allow small molecules to pass through Kind of like the latex of a water balloon Can you name some things with membranes?

Carbohydrate side chain Fig. 6-7 (a) TEM of a plasma membrane Outside of cell Inside of cell 0.1 µm Carbohydrate side chain Hydrophilic region Hydrophobic region Hydrophilic region Phospholipid Proteins (b) Structure of the plasma membrane

10 m 1 m 0.1 m 1 cm 1 mm 100 µm 10 µm 1 µm 100 nm 10 nm 1 nm 0.1 nm Fig. 6-2 10 m Human height 1 m Length of some nerve and muscle cells 0.1 m Unaided eye Chicken egg 1 cm Frog egg 1 mm 100 µm Most plant and animal cells Light microscope 10 µm Nucleus Most bacteria 1 µm Mitochondrion 100 nm Smallest bacteria Electron microscope Viruses Ribosomes 10 nm Proteins Lipids 1 nm Small molecules 0.1 nm Atoms

4.1 Introduction to the Cell pp. 69-72 Summary: All cells have membranes, usually prokaryotic cells are more simple. (small, no membrane organelles)