PPT-TREPONEMA PALLIDIUM e s una bacteria Gram Negativa, espiroqueta altamente contagiosa,

Existen por lo menos tres subespecies conocidas T pallidum pallidum causante de la sífilis T pallidum pertenue causante de la frambesia también llamada buba o pián y T pallidum endemicum. Mrs. Stewart. Medical Interventions. Central Magnet School. 2 Classes of Bacteria. Gram (-) . Thin layer of . peptidoglycan. Lipopolysaccharides. (. endotoxins. ). Stain red. Gram (+). Thick layer of . Last day. Brief . introduction to bacteria, . Archaebacteria. , and bacterial culturing media. . Today. We will start by looking at our cultures, and providing colony descriptors. . We . will learn about the Biology of Bacteria. Structure and Function. 2. Prokaryote & Eukaryote. Evolution. 3. Cellular Evolution. Current evidence indicates that . eukaryotes evolved from prokaryotes. between 1 and 1.5 billion years ago. Two theories:. Physical differences & clinical . signifigance. . . Figure 4.8b. Gram- positive bacteria. Gram-negative bacteria. Figure 4.8a. Gram-Positive cell walls. Teichoic acids:. Lipoteichoic acid links to plasma membrane. continued. Gram Stain. When bacteria are treated with a dye made up of crystal violet and iodine they react in one of two ways. . Bacteria . cells that appear purple are gram-positive and bacteria that change to pink are gram-negative. .  . Bacteria form a large group of parasitic, saprophytic, and free-living microorganism .  . 1. Bacterial cell wall (protects against osmotic damage).  . Bacterial cell is prokaryotic. Contains high concentration . 2. Prokaryote & Eukaryote. Evolution. 3. Cellular Evolution. Current evidence indicates that . eukaryotes evolved from prokaryotes. between 1 and 1.5 billion years ago. Two theories:. 1. . Infolding theory. Internal Structures:. cytoplasm. nucleoid. ribosomes. Boundaries:. cell membrane. cell wall. capsule. Appendages:. flagellum. pili. Shapes of Bacteria. Bacteria Identification Criteria. Shapes. Lack a nucleus. DNA is naked, a single loop not bound in a chromosome. May contain plasmids (small circular fragments of DNA). Have ribosomes, but no other organelles.. DNA present as a long circular molecule.. “We learn . . . 10% of what we read, 20% of what we hear, 30% of what we see, 50% of what we see and hear, 70% of what we discuss, 80% of what we experience, 95% of what we teach others.”. ~ William Glasser. and . Function. Bacterial . Form . and Function. A. . Structures common to . all. bacterial cells. 1. . Cell membrane. 2. . Cytoplasm. 3. . Ribosomes. 4. . One (or a few) . chromosomes. Bacterial Form . 1 The slide is washed in water; excess water is removed using a blotting paper, dried in air and heat fixed before observing under microscope. Those bacteria that hold on to primary dye-iodine comple Size of a Bacterial Cell: . There are great variations in size of bacteria. . They . measure from 0.75 µ to 1.5 µ but on an average each cell of bacterium measures about 1.25 µ to 2 µ . ( . in . diameter). . Gram Positive. Gram Negative. Gram-Positive bacteria. Gram-Negative bacteria. Cell Wall. A single-layered, smooth cell wall.  A double-layered, wavy cell-wall. Cell Wall thickness. The thickness of the cell wall is 20 to 80 .