chapter 2
DESCRIPTION
Chapter 2 Lecture. Chapter 2. The Cell. Frederic Martini Michael Timmons Robert Tallitsch. Introduction. Cell theory: Cells are the smallest structural units that perform all vital functions. The Study of Cells. The study of cells is cytology : Light microscopy - PowerPoint PPT PresentationTRANSCRIPT
HUMAN ANATOMYFifth Edition
Chapter 1 Lecture
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Chapter 2 Lecture
Chapter 2The Cell
Frederic MartiniMichael TimmonsRobert Tallitsch
Introduction
• Cell theory: – Cells are the smallest structural units that
perform all vital functions.
Figure 2.1a,b,c Different Technique, Different Perspective
The Study of Cells
• The study of cells is cytology:– Light microscopy – Transmission electron microscopy – Scanning electron microscopy
Figure 2.3 Anatomy of a Typical Cell
Cellular Anatomy
Cells have four types of component:
1) Membranes2) Organelles3) Cytoplasm4) inclusions
Figure 2.4 A Flow Chart for the Study of Cell Structure
Cellular Anatomy
Cell Structure
PLAY Cell Structure
This movie reviews cell structure.
Figure 2.5 The Cell Membrane
The Cell Membrane
The Cell Membrane
• Major functions of the cell membrane can be described:– Regulation of exchange with the
environment– Receptors and ID
Figure 2.6 Diffusion across the Cell Membrane
Membrane Permeability: Passive Processes
• Diffusion
• Osmosis
• Facilitated Diffusion
Membrane Permeability: Active Processes
• Active transport uses enzymes and carrier proteins:– Ions pumps are carrier proteins for charged
particles.– Ions moved regularly by active transport
include Na+, Ca2+, Mg2+, K+
– Ion pumps are specific. – An ion pump that moves two ions
simultaneously in opposite directions is called an exchange pump.
Figure 2.7a Pinocytosis
Membrane Permeability: Active Processes
Figure 2.7b Phagocytosis
Membrane Permeability: Active Processes
Figure 2.8 Receptor-Mediated Endocytosis
Membrane Permeability: Active Processes
Cytoplasm
• The cytoplasm is the general term for the material inside the cell.– It is a fluid very high in protein. – The cytosol is the intracellular fluid:
• It is high in potassium ions.• It contains an overall negative charge.
– Transmembrane potential
• It contains high concentrations of proteins.
– Organelles are structures within the cyto-plasm that have a particular function and very distinct structure.
Nonmembranous Organelles
• The cytoskeleton:– Microfilaments– Microtubules
• Microvilli
QuickTime™ and a decompressor
are needed to see this picture.
Figure 2.9 The Cytoskeleton
Nonmembranous Organelles
Figure 2.10 Centrioles and Cilia
Nonmembranous Organelles
• Centrioles
• Cilia
• Flagella
Figure 2.11 Ribosomes
Nonmembranous Organelles
• Ribosomes:– 60% RNA and 40% protein– Free ribosomes:
• Float in the cytoplasm
– Fixed ribosomes:• Are attached to the endoplasmic reticulum
Figure 2.12 Mitochondria
Membranous Organelles
• Mitochondria are double membraned organelles. – Cristae are the folds of the inner membrane – Inner fluid is the matrix.
Membranous Organelles
• The nucleus is the control center of the cell.– Nucleoplasm– Nuclear envelope – Perinuclear space– Nuclear pores– Nuclear matrix
Figure 2.13a The Nucleus
Membranous Organelles
Figure 2.14 Chromosome Structure
Membranous Organelles: Nucleus
• Chromosomes: – DNA wrapped
around proteins called histones.
– Nucleosomes– Chromatin
Membranous Organelles
• The ER has four major functions:– Synthesis of all classes of macromolecules– Storage of the manufactured molecules– Transport of substances from on area of the
cell to another– Enzymes in the lumen of the ER provide
detoxification
Figure 2.15 The Endoplasmic Reticulum
Membranous Organelles
Figure 2.16b The Golgi Apparatus
Membranous Organelles
• The three main functions of the Golgi apparatus:– Synthesis and
packaging of secretions.
– Packaging of enzymes for use in the cytosol.
– Renewal and modification of the cell membrane.
Figure 2.18 Lysosomal Functions
Membranous Organelles
• Lysosome function in three manners:
1. Fuse with phagosomes to digest solid materials.
2. Fuse with and recycle damaged organelles.
3. Sometimes rupture a process resulting in autolysis.
Figure 2.19 Cell Attachments
Intercellular Attachment
Figure 2.20 The Cell Life Cycle
The Cell Life Cycle
Figure 2.21 DNA Replication
DNA Replication
Figure 2.22a
Interphase
Figure 2.22b,c
Prophase
Figure 2.22d,e
Metaphase and Anaphase
Figure 2.22f,g
Telophase and Cytokinesis