Tham khảo tài liệu 'saladin anatomy and physiology the unity of form and function episode 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | I Text Saladin Anatomy Physiology The Unity of Form and Function Third Edition 3. Cellular Form and Function The McGraw-Hill Companies 2003 Chapter 3 Cellular Form and Function 123 Figure Microtubules. a A microtubule is composed of 13 protofilaments. Each protofilament is a spiral chain of globular proteins called tubulin. b One of the nine microtubule pairs that form the axonemes of cilia and flagella. c One of the nine microtubule triplets that form a centriole. Chapter 3 Table Summary of Organelles and Other Cellular Structures Structure Appearance to TEM Function Plasma membrane figs. and Two dark lines at cell surface separated by narrow light space Prevents escape of cell contents regulates exchange of materials between cytoplasm and extracellular fluid involved in intercellular communication Microvilli figs. and a-b Short densely spaced hairlike processes or scattered bumps on cell surface interior featureless or with bundle of microfilaments Increase absorptive surface area some sensory roles hearing equilibrium taste Cilia figs. and Long hairlike projections of apical cell surface axoneme with 9 2 array of microtubules Move substances along cell surface some sensory roles hearing equilibrium smell vision Flagellum Long single whiplike process with axoneme Sperm motility Nucleus figs. and Largest organelle in most cells surrounded by double unit membrane with nuclear pores Genetic control center of cell directs protein synthesis Rough ER fig. Extensive sheets of parallel unit membranes with ribosomes on outer surface Protein synthesis and manufacture of cellular membranes Smooth ER fig. Branching network of tubules with smooth surface no ribosomes usually broken into numerous small segments in TEM photos Lipid synthesis detoxification calcium storage Ribosomes fig. Small dark granules free in cytosol or on surface of rough ER Interpret the genetic code and synthesize polypeptides Golgi .
