BIOL 1202 Chapter : Ch 27
Document Summary
Concept 27. 1 structural and functional adaptations contribute to prokaryotic success. Prokaryotes are unicellular: some colonial forms (individuals that live in contact with one another but each cell is still independent, range in size from 1-5 micrometers, thiomargarita namibiensis (750 micrometers, no membrane-bound organelles, circular chromosomes. Prokaryotic cells have a variety of shapes. The three most common are spheres (cocci), rods (bacilli), and spirals (spirilli) Cell wall: maintains cell shape, provides physical protection, prevents cells from bursting in a hypotonic environment, composed of peptidoglycan in bacteria, may also have an outer phospholipid membrane. A capsule (a sticky layer of polysaccharide or protein) may cover the cell wall of many prokaryotes. Fimbriae and pilli allow prokaryotes to stick to their substrate or other individuals in a colony. Gram-negative bacteria have ___ peptidoglycan then gram-positive cell and their cell walls are ___ complex structurally. Motile bacteria are able to move in their environment by means of bacterial flagellae: structurally different from eukaryotic flagella.