* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Cell Division and Mitosis
Survey
Document related concepts
Tissue engineering wikipedia , lookup
Cytoplasmic streaming wikipedia , lookup
Cell growth wikipedia , lookup
Cell encapsulation wikipedia , lookup
Extracellular matrix wikipedia , lookup
Cellular differentiation wikipedia , lookup
Cell culture wikipedia , lookup
Signal transduction wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Cell nucleus wikipedia , lookup
Cell membrane wikipedia , lookup
Cytokinesis wikipedia , lookup
Transcript
Cell Structure and Function Starr/Taggart’s Biology: The Unity and Diversity of Life, Chapter 4 9e Key Concepts: All organisms are composed of cells The cell is the basic unit of life All cells have a double-layered plasma membrane Membranes consist largely of phospholipid and protein molecules Key Concepts: Organelles are membrane-bound compartments inside eukaryotic cells Prokaryotic cells do not have organelles When cells grow, they increase faster in volume than in surface area Different microscopes modify light rays or accelerated beams of electrons that allow small images to be observed Basic Aspects of Cell Structure and Function Plasma membrane Lipid bilayer Proteins • Channels, transport, pumps, receptors DNA-containing region Cytoplasm Cell Size and Shape Surface to Volume Ratio Volume increases more rapidly than surface area Restrictions on size and shape Microscopes A - Light microscope B - Transmission Electron Microscope C - Scanning Electron Microscope Defining Structures of Eukaryotic Cells A Plant Cell An Animal Cell Major Cellular Components Nucleus Ribosomes Endoplasmic reticulum Smooth and Rough Golgi body Various vesicles Mitochondria Cytoskeleton Components of the Nucleus Nuclear envelope - Surrounds nucleus Nucleoplasm - Fluid interior portion Chromosome - One DNA molecule and associated proteins Chromatin - Total collection of all DNA molecules and associated proteins Nucleolus - RNA and proteins that will be assembled into ribosomal subunits The Nuclear Envelope Double - membrane system Two lipid bilayers Surrounds nucleoplasm Pores allow exchange The Cytomembrane System Organelles in which lipids are assembled and proteins are produced and modified Endoplasmic reticulum Golgi bodies Vesicles The Endoplasmic Reticulum Rough and Smooth Presence or absence of ribosomes Rough: Proteins Smooth: Lipids Rough ER Smooth ER Golgi Bodies Enzymatic finishes on proteins and lipids, and packaging in vesicles Vesicles Lysosomes Peroxisomes Transport Mitochondria Production of ATP Double-membrane system Two distinct compartments Have their own DNA Divide on their own Have ribosomes Chloroplast Found in photosynthetic eukaryotes Two outer membranes Semifluid stroma Inner thylakoid membrane system Photosynthetic pigments Components of the Cytoskeleton Microtubules Tubulin subunits Cell division and movement Microfilaments Actin subunits Movement and shape Components of the Cytoskeleton Intermediate Filaments Only in animal cells of specific tissues Mechanically strengthen cells or cell parts and help maintain shape Six known groups Structural Basis of Cell Motility Three Mechanisms Length of microtubule can change Parallel microtubules slide in opposite directions Shunting of organelles Sliding mechanism for beating of flagella Cell Surface Specializations Eukaryotic Cell Walls A single-celled protist Plant Cell Wall Cell secretions form lamella Plasmodesmata (channels) Primary and Secondary walls Plant Cell Walls Deposition of layers inside primary wall Stiffen wall Maintain shape Cell-to Cell Junctions Plants Plasmodesmata Animals Tight Junctions Adhering Junctions Gap Junctions Prokaryotic Cells The Bacteria No nucleus - DNA in free cytoplasm Smallest of all cells Most have a cell wall Polysaccharides cover cell wall of many species No membrane-bound organelles Flagella lack 9+2 array of microtubules Bacterial Cell In Conclusion The cell theory states All living cells are composed of cells The cell is the smallest unit of life New cells arise only from pre-existing cells Cells have a plasma membrane, cytoplasm, and a region of DNA The plasma membrane maintains the cell as a separate entity In Conclusion The cytoplasm is all the fluids, ribosomes and organelles in eukaryotic cells between the nucleus and plasma membrane Membranes consist of a bilayer of lipids and proteins embedded in the bilayer or attached to the surface. Proteins carry out most of cell membrane functions In Conclusion Membranes divide functional compartments into organelles Prokaryotes do not have organelles Organelle membranes separate metabolic reactions developed by M. Roig