ELAINE N. MARIEB EIGHTH EDITION 3 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by Jerry L. Cook, Sam Houston University ESSENTIALS OF HUMAN ANATOMY & PHYSIOLOGY PART A Cells and Tissues

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  This Power Point presentation has been adapted to fit our curriculum.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Anatomy of the Cell  Cells are not all the same  All cells share general structures  Cells are organized into three main regions  Nucleus  Cytoplasm  Plasma membrane Figure 3.1a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Nucleus  Control center of the cell  Contains genetic material (DNA)  Three regions  Nuclear membrane  Nucleolus  Chromatin Figure 3.1b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Nucleoli  Nucleus contains one or more nucleoli  Sites of ribosome production  Ribosomes then migrate to the cytoplasm through pores in nuclear membrane

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chromatin  Composed of DNA and protein  Scattered throughout the nucleus  Chromatin condenses to form chromosomes when the cell divides

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane  Maintains boundary for cell contents  Double phospholipid layer  Hydrophilic heads  Hydrophobic tails  Also contains protein, cholesterol, and glycoproteins MEMBRANE STRUCTURE ANIMATION PRESS TO PLAY

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Figure 3.2

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Specializations  Microvilli  Finger-like projections of cell membrane that increase surface area for absorption  Found in small intestine where nutrients are absorbed Figure 3.3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Specializations  Membrane junctions  Tight junctions – impermeable junctions that bind cells into leakproof sheets. Where in the body might you find these? Figure 3.3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Specializations  Membrane junctions  Desmosomes – anchoring junctions that prevent cells subjected to mechanical stress from being pulled apart. Where might you find these? Figure 3.3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Plasma Membrane Specializations  Membrane junctions  Gap Junctions – allow communication between cells; commonly found in heart muscle Figure 3.3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasm  Material outside the nucleus and inside the plasma membrane  Cytosol  Fluid that suspends other elements  Organelles  Metabolic machinery of the cell  Inclusions  Non-functioning units

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles Figure 3.4

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Mitochondria  “Powerhouses” of the cell  Carry out reactions where oxygen is used to break down glucose and produce ATP for cellular energy

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Mitochondria  Where in the body would you be likely to find large numbers of mitochondria in the cells? Why?

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Ribosomes  Made of protein and ribosomal RNA  Sites of protein synthesis  Found at two locations  Free in the cytoplasm  Attached to rough endoplasmic reticulum

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Endoplasmic reticulum (ER)  Fluid-filled tubules for carrying substances  Two types of ER  Rough Endoplasmic Reticulum  Studded with ribosomes; involved in protein synthesis  Site where building materials of cellular membrane are formed Where in the body might you find cells with lots of RER?

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Smooth Endoplasmic Reticulum  Functions in cholesterol synthesis and breakdown, fat metabolism, and detoxification of drugs Where in the body might you find cells with lots of SER?

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Endoplasmic reticulum  What type of endoplasmic reticulum would you find in the testes where testosterone is produced? Why? Hint: testosterone is a steroid.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Golgi apparatus  Modifies and packages proteins (Fed-ex)  Looks like a stack of pancakes with vesicles  Produces different types of packages  Secretory vesicles  Cell membrane components  Lysosomes

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Golgi Apparatus Figure 3.6

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Lysosomes  Contain enzymes that digest cell waste  Found in WBCs – digest bacteria  Peroxisomes  Membranous sacs of oxidase enzymes  Detoxify harmful substances  Break down free radicals (highly reactive chemicals)  Replicate by pinching in half

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lysosomes  If a cell is injured the lysosomal membrane becomes fragile. What might happen to a cell if a lysosome was to rupture? Why?

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Cytoskeleton  Network of protein structures that extend throughout the cytoplasm  Provides the cell with an internal framework Figure 3.7a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cytoplasmic Organelles  Cytoskeleton  Three different types (from smallest to largest)  Microfilaments  Intermediate filaments  Microtubules Figure 3.7b–d

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Microtubules are found in centrioles  Rod-shaped bodies made of microtubules  Direct formation of mitotic spindle during cell division

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Intermediate filaments help form desmosomes. What are desmosomes and where are they found?

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Microfilaments  Examples are actin and myosin which are found in muscle cells  Involved in muscle contraction

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cellular Projections  Not found in all cells  Used for movement  Cilia moves materials across the cell surface (in trachea, fallopian tubes)  Flagellum (longer than cilia) propels the cell (in sperm)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cell Diversity Figure 3.8a–b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cell Diversity Figure 3.8c

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cell Diversity Figure 3.8d–e

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cell Diversity Figure 3.8f–g