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AEDeCadiz, PhD_2019 Lecture 2 Structure and...

AEDeCadiz, PhD_2019 Lecture 2 Structure and Function of Microbial Cells © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  Learning Objectives AEDeCadiz, PhD_2019 1. Compare and contrast the major differences between prokaryotic and eukaryotic cells including major organelles. 2. Describe the structure and assess the roles of each bacterial organelle 3. Explain how the structures of archaeans differ from bacteria © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  I. Cells of Bacteria and Archaea AEDeCadiz, PhD_2019 2.1 Cell Morphology 2.2 The Small World © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  2.1 Cell Morphology: Cell shape AEDeCadiz, PhD_2019 Major morphologies of prokaryotic cells (Figure 2.1) coccus (pl. cocci): spherical or ovoid rod/bacillus: cylindrical spirillum: curved or spiral Some stay grouped/clustered after cell division in characteristic arrangements (e.g., chains of Streptococcus, cubes of Sarcina, grapelike clusters of Staphylococcus). © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  2.1 Cell Morphology: Cell Shape AEDeCadiz, PhD_2019 Cells with unusual shapes spirochetes (tightly coiled), appendaged bacteria, and filamentous bacteria Many variations on basic morphological types known © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  2.1 Cell Morphology AEDeCadiz, PhD_2019 Morphology typically does not predict physiology, ecology, phylogeny, or other properties of a prokaryotic cell. May be selective forces involved in setting the morphology optimization for nutrient uptake (small cells and high surface-to-volume ratio, such as appendaged cells) swimming motility in viscous environments or near surfaces (helical or spiral-shaped cells) gliding motility (filamentous bacteria) © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  2.2 The Small World AEDeCadiz, PhD_2019 Size range for prokaryotes: 0.2 µm to >700 µm in diameter (Table 2.1) Most cultured rod-shaped bacteria are between 0.5 and 4.0 µm wide and 600 µm in diameter © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  AEDeCadiz, PhD_2019 © 2019 Pearson Education Ltd. Table 2.1 For UPMindanao students use only. Do not share or repost- AEdeCadiz  AEDeCadiz, PhD_2019 © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  AEDeCadiz, PhD_2019 © 2019 Pearson Education Ltd. Figure 2.2 For UPMindanao students use only. Do not share or repost- AEdeCadiz  2.2 The Small World AEDeCadiz, PhD_2019 Surface-to-volume ratios, growth rates, and evolution advantages to being small (Figure 2.3) more surface area relative to cell volume than large cells (i.e., higher S/V ratio). support greater nutrient and waste product exchange per unit cell volume tend to grow faster than larger cells Mutations lead to faster evolution. Eukaryotic cells adapt slower. © 2019 Pearson Education Ltd. For UPMindanao students use only. Do not share or repost- AEdeCadiz  AEDeCadiz, PhD_2019 © 2019 Pearson Education Ltd. Figure 2.3 For UPMindanao students use only. Do not share or repost- AEdeCadiz  2.2 The Small World AEDeCadiz, PhD_2019 Lower limits of cell size Cellular organisms