* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Chapter 7 Body Systems
Survey
Document related concepts
Biochemical switches in the cell cycle wikipedia , lookup
Cytoplasmic streaming wikipedia , lookup
Cell encapsulation wikipedia , lookup
Extracellular matrix wikipedia , lookup
Cellular differentiation wikipedia , lookup
Cell culture wikipedia , lookup
Signal transduction wikipedia , lookup
Cell growth wikipedia , lookup
Cell nucleus wikipedia , lookup
Cell membrane wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Cytokinesis wikipedia , lookup
Transcript
Chapter 3 Anatomy of Cells Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 1 Anatomy of Cells • Cell Structure • Cellular Components Structure Function Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 2 Table 3-2 Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 3 Functional Anatomy of Cells • The typical cell (Figure 3-1) – generic cell Varies in size; all are microscopic (Table 3-1) Varies in structure and function (Table 3-2) Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 4 Typical Cell – Fig. 3-1 Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 5 Typical or Composite Cell – Fig. 3-1 Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 6 Cell Structures • Plasma membrane—separates the cell from its surrounding environment • Cytoplasm—thick gel-like substance inside of the cell composed of numerous organelles suspended in watery cytosol; each type of organelle (“little organ”) is suited to perform particular functions (Figure 3-2) • Nucleus—large membranous structure near the center of the cell Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 7 Cell Membranes • Plasma membrane (Figure 3-3) • Membranous organelles – sacs and canals made of the same material as the plasma membrane Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 8 Cell Membranes • Structure – is a double layer of phospholipid molecule Phospholipid • Heads are hydrophilic (water-loving) • Tails are hydrophobic (water-fearing) Cholesterol molecules are scattered among the phospholipids to allow the membrane to function properly at body temperature Membrane Proteins • Controls what moves through the membrane • Act as i.d. markers • Act as receptors Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 9 Cell Membrane • Membrane Function To keep cellular components inside the cell and extracellular material outside the cell Controls what moves into and out of the cell Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 10 Cytoplasm and Organelles • Cytoplasm – gel-like internal substance of cells that includes many organelles suspended in watery intracellular fluid called cytosol Cytosol – the watery intracellular fluid Organelles – “little organs” each have a particular structure and function • Know the function of each organelle and be able to identify it in a generalized figure of the cell Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 11 Endoplasmic Reticulum (Figure 3-5) • Function: Synthesis of proteins that will be excreted from the cell (rough ER) and synthesize lipids for the cell membrane, steroid hormones, and certain carbohydrates, removes and stores Ca2+ from the cell’s interior Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 12 Endoplasmic Reticulum • Two types of ER: Smooth ER – do not have ribosomes attached • Synthesizes certain lipids and carbohydrates and creates membranes for use throughout cell • Removes and stores Ca++ from cell’s interior. Rough ER – have ribosomes attached to the outer surface • Ribosomes synthesize proteins, which move toward the Golgi apparatus and then eventually leave the cell • Function in protein synthesis and intracellular transportation Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 13 Ribosomes • Function: the site of protein synthesis Attached to rough ER or scattered in the cytoplasm • Structure: made of two pieces, a large subunit and a small subunit • Ribosomes in the endoplasmic reticulum make proteins for “export” or to be embedded in the plasma membrane; free ribosomes make proteins for the cell’s domestic use Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 14 Golgi Apparatus • Function: Synthesizes carbohydrates, processes proteins from the ER; the cell’s “post office” • Structure: cisternae stacked on one another and located near the nucleus • Processes protein molecules from the endoplasmic reticulum (Figure 3-8) Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 15 Figure 3-8. The Cell’s Protein Export System Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 16 Lysosomes • Function: Bags of digestive enzymes break down defective cell parts and ingested particles; a cell’s “digestive system” • Structure: Made of microscopic membranous sacs that have “pinched off” from Golgi apparatus Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 17 Proteasomes • Function: Hollow protein cylinders that break down abnormal/misfolded proteins and normal proteins no longer needed by the cell Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 18 Peroxisomes • Function: contain enzymes that detoxify harmful substances Often seen in kidney and liver cells Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 19 Mitochondria • Function: A cell’s “power plant”; the site of ATP synthesis • Mitochondrial DNA: Each mitochondrion has a DNA molecule, allowing it to produce its own enzymes and replicate copies of itself Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 20 Nucleus • Definition—spherical body in center of cell; enclosed by an envelope with many pores • Function: Contains DNA (genetic code) – the “brain” of the cell, dictates protein synthesis Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 21 Nuclear Structure • Nuclear Envelope – nuclear membrane, has nuclear pores (controls entrance in and out of the cell) • Nucleoplasm – nuclear substance • Chromatin – the DNA in non-dividing cells • Nucleolous – found in the nucleus, synthesizes rRNA and combines it with protein to form ribosomes Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 22 Nucleus • Contains DNA (heredity molecules), which appear as the following: Chromatin threads or granules in nondividing cells Chromosomes in early stages of cell division Functions of nucleus are functions of DNA molecules; DNA determines both structure and function of cells and heredity Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 23 Cytoskeleton • Function: acts as a framework to support the cell and its organelles; involved in cell movement; forms cell extensions Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 24 Cytoskeleton • Cell fibers – 3 types Microfilaments Intermediate Filaments Microtubules Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 25 Microfilaments • Smallest cell fibers “Cellular muscles” Made of thin, twisted strands of protein molecules that lie parallel to the long axis of the cell Microfilaments can slide past each other, causing shortening of the cell Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 26 Intermediate Filaments • Twisted protein strands slightly thicker than microfilaments; form much of the supporting framework in many types of cells Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 27 Microtubules • Tiny, hollow tubes that are the thickest of the cell fibers • Function: move things around in the cell Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 28 Centrosome • Also called the microtubule-organizing center (MTOC) • Plays an important role during cell division • The general location of the centrosome is identified by the centrioles Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 29 Cell Extensions • Cytoskeleton that forms projections that extend the plasma membrane outward to form tiny, fingerlike processes Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 30 Three Types of Cell Extensions • Microvilli – founds in epithelial cells that line intestines, increase surface area for absoption • Cilia – short and numerous, move substances along the surface of a cell • Flagella – involved in total cell movement; found on human sperm cells Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 31 The Big Picture • Review • Conclusions Mosby items and derived items © 2007, 2003 by Mosby, Inc. Slide 32