Chapter 6 Cells Prokaryote no true nucleus o Bacteria 10 microns Eukaryotic true nucleus o Protista animals plants fungi 100 microns Plasma membrane composed of a bilayer of phospholipids and interspersed proteins Cell theory o All living things are composed of cells Schwann and Scheiden o All cells come from pre existing cells Virchow DNA is double stranded thymine RNA is single stranded uracil Cells are microscopic as cells get bigger the amount of cytoplasm will increase faster than the cell membrane o Cytoplasm in the cell produces waste o Ribosomes composed of large O and o subunit function is protein synthesis o Nucleoid the region where you find chromosomes o Endoplasmic Reticulum rough ER ribosomes site of protein synthesis smooth ER lipid and carb synthesis once made they are packaged into transport vesicles o Transport vesicle transport contents to Golgi apparatus o Golgi apparatus composed of roughly 5 7 cisternae cis face closest to nucleus trans face shipping side place of assembly o Protein carb might combine to form glycoprotein o Secretory vesicle moves away from trans side of Golgi and fuses with plasma membrane of cell pore develops where fusion happens and glycoproteins are secreted from the cell trans side can also produce lysosomes o Lysosomes organelle of endomembrane system large vesicle contains power hydrolytic enzymes can break two monomers apart by adding water hydrolysis intracellular digestion taken into the cell by phagocytosis cell eating plasma membrane forms extension called pseudopodia and takes bacteria into cell phagocytic vesicle around bacteria in cell and meets with lysosome where it is then o o o o o o o o digested we digest with extracellular digestion Vacuole large vesicle Autophagy self eating destroy defective organelles Endomembrane system membrane within the cell Nucleolus the location of ribosome synthesis Chromatin what chromosomes are made of Lumen the space in between Nuclear Pores for entering and exiting Mitochondrion not part of endomembrane system site of cellular respiration involves chemical reactions that use oxygen and release carbon dioxide CH20 O C02 H20 ENERGY energy used to make ATP which is energy money o Lynn Margulis Endosymbiot one cell living inside the cytoplasm of another theory mitochondria and chloroplasts used to be free living bacteria mitochondria was an aerobic bacterium can use oxygen to perform cellular respiration o Chloroplast organelle found in photosynthetic eukaryotic cells plants kingdom Plantae algae group Protista location of photosynthesis in eukaryotic cells CO2 H2O sunglight CH20 O2 o Peroxisomes destroy peroxides hydrogen peroxide H O O H H2O2 any molecule with an O O single bond important in fatty acid metabolism broken apart two carbons at a time as a fuel to make ATP in mitochondria Cytoskeleton of Eukaryotic Cells framework that structures cytoplasm of cells can change the shape of a cells allow it to move etc 1 Microtubules largest formed from the protein tubulin maintain cell shape and important in changing cell shape track for motor proteins o Cilia and flagella contain microtubules at the base have a basal body respiratory system bronchial tubes then trachea lined with a layer of cells which have cilia on them cells are anchored down and cilia propels mucus helps to clean respiratory system 9 2 arrangement of microtubules ex animals Protista fungi plants 2 Intermediate filaments strands made of protein keratin fingernails and hair made out of this important in anchoring parts of the cell together 3 Microfilaments smallest composed of protein actin important in movement in division they appear in between the two cells compress the central region of the cell until eventually they split involved in muscle contraction Proteins and Nucleic Acids are structurally polarized Centrosome clear cytoplasm microtubular organizing center organizes the development and changing of microtubules in the cell Centrioles composed of 9 triplets of microtubules 2 centrioles in the centrosome in animal cells help direct the formation of microtubules Cell Surfaces and Junctions o Plants primary cell wall structure made of cellulose prevent cell from exploding few plant cells have secondary cell wall inside of cell wall thicker and stronger than the primary cell wall cells of wood have these composed of cellulose and hardening substance called lignin important in making paper makes cellulose stronger and harder space in between cells middle lamella pectin polysaccharide hold cells together o Animals do not have a cell wall but have extracellular matrix composed of glycoproteins proteins with small carbohydrates attached to it ex collagen proteoglycan carbohydrate core with amino acid chains guides cell migration cellular adhesion CAMS cellular adhesion molecules cellular recognition cells of immune system can recognize foreign objects cancer cells loose cellular adhesion CAMS are defective can undergo metastasis new cancer that develops away from original cancer o Plant Cellular junctions plasmadesmata connection between two adjacent plant cells o Animal cell junction gap junction allows ions etc to go from one animal cell to the next cardio muscle cells are all united by gap junctions when one contracts all of its neighbors can contract at the same time tight junctions found in epithelia layers of cells on body surfaces etc skin inner lining of mouth plasma members of epithelia with fuse together to form tight junction desmosome junction rivet or spot weld composed of series of proteins in plasma membranes anchor cells of an epithelia together to make very strong found commonly in epithelia that endure a lot of stretch ex urinary bladder Chapter 7 The Plasma Membrane o Fluid Mosaic Model 1972 talks about the structure of the plasma membrane The plasma membrane is composed of phospholipid bilayer with interspersed proteins o Plasma membrane is like a fluid components can move around mainly composed of phospholipids arranged in a bilayer mainly lipids o To keep lipids from solidifying make sure fatty acids of phospholipids are at least partially unsaturated allowing them to move more freely another way is to break up fatty acid tails by cholesterol molecules o Fish that live in water that is very warm there are more saturated fatty acids to ensure that it is not too liquidy o Proteins in plasma membrane can move around freely like icebergs but can also be anchored to the cytoskeleton Mosaic o Proteins can be