Cellular respiration atp chlorophyll green pigment

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cellular respiration -> ATP chlorophyll (green pigment) + enzymes + molecules = photosynthetic production of sugar Endosymbiont theory: early ancestor of eukaryotic ells engulfed an oxygen-using nonphotosynthetic prokaryotic cell -> mitochondria + chloroplast have 2 double membranes, contain ribosomes, and a circular DNA
Cytoskeleton : provide mechanical support & maintain shape & motility Microtubules Microfilaments structure: hollow tubules made of tubulin functions: - Maintenance of cell shape - Cell motility (cilia/flagella) - Chromosome movements in cell division - Organelle movements “9+2” pattern: 9 doublets of microtubules arranged in a ring + 2 single rings in the center structure: 2 intertwined strands of actin functions: -maintenance of cell shape -changes in cell shape - Muscle contraction - cytoplasmic streaming - cell motility (pseudopodia) - cell division (cleavage furrow formation) eview question: tell how the receptor protein is made and how it can get put into the plasma membrane . mRNA -> ribosome -> bound ribosome (guided to the ER by signal recognition particle) . Newly synthesized protein travels to Glolgi in a vesicle from ER . at Golgi, the protein gets sorted (according to different “tags” on the proteins) -> travels to the plasma membrane in a transport vesicle . Transport vesicle fuses with the plasma membrane
membrane Fluid mosaic model: membrane is a structure with a “mosaic” of various proteins embedded to a double layer. Membranes are fluid because of the lateral movements of phospholipids within the membrane. The mixing of the mouse and human membrane proteins showed that membrane proteins move around within the membrane factors affecting membrane fluidity: - Phospholipid tails – saturated vs. unsaturated hydrocarbon chains -> if the membrane has a lot of unsaturated tails, it remains fluid at lower temperature because of kinks -> they cant pack together as closely - steroid cholesterol – wedged between phospholipids -> less fluid at high temperatures (restrain phospholipid movements) and less rigid at low temperatures (hinder close packing) Functions: transport enzymatic activity signal transduction cell-cell recognition intercellular joining attachment to the cytoskeleton Selective permeability Active transport Passive transport expend energy (ATP) allows cells to maintain internal concentrations of small solutes sodium-potassium pump no energy needed diffusion : the movement of molecules down their own concentration gradient osmosis : diffusion of free water concentration down the concentration gradient - isotonic : no net movement of water - hypertonic : solution has higher concentration of solutes; the cell will lose water and shrivel (animal) and become plasmolyzed (plant) - hypotonic : the cell has higher concentration of solutes; the cell will gain water and become lysed (animal) or turgid (plant) facilitated diffusion: help polar molecules/ions diffuse passively; ion channels, aquaporins, carrier proteins Cotransport : a single ATP-powered pump that transports a specific solute

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