01:119:101 Lecture Notes - Lecture 1: Photosynthetic Pigment, Cell Membrane, Thermophile
8 Dec 2015
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Document Summary
Structural and functional adaptations contribute to prokaryotic success first organism to inhabit earth 3. 6 billion years ago: have since been subjected to natural selection in all kinds of environment leading to their enormous diversity. Structures unicellular very small with diameter of . 5-5 um. Well organized, achieving all of an organisms life function within a single cell cell wall: maintains cell shape, protects cell, prevents it from busting in a hypotonic environment or shrinking in hypertonic (plasmolyze) Most bacteria cell walls contain peptidgylcan: polymer composed of modified sugars cross linked by short polypeptides a staining method that distinguishes between two kinds of bacteria cell wells. Many prokaryotes are capable of taxis directed movement toward or away from a stimulus such as oxygen or nutrients (positive chemotaxis) or away from a toxic substance (negative chemotaxis) Simpler than eukaryotes in both their internal structure and physical arrangement of their dna.
