Active Transport – Essay

Active transport: requires that a cell expend energy to move molecules across a membrane against the solute’s concentration gradient (the side where it is more concentrated) Feedback inhibition: Metabolic reaction is blocked by its products. A product acts as an inhibitor of one of the enzymes in the pathway to regulate metabolism. Centriole: a structure in an animal cell composed of microtubule triplets arranged in a 9+0 pattern. An animal usually has a pair of centrioles within each of its centrosomes. Chloroplasts: photosynthesizing organelles of all photosynthetic eukaryotes. Competitive inhibition: resembles the enzyme’s normal substrate and competes with the substrate for the active site on the enzyme. Countercurrent exchange: the transfer of a substance from a fluid or volume of air moving in one direction to another fluid or volume of air moving in the opposite direction Cytochrome system: The cytochrome system is found in the many cristae of mitochondria, which are tiny stalked particles found on its outer layer. Degradative: The reduction of a chemical Compound to one less complex, as by splitting off one or more groups. Degeneration Elucidate: to make clear Entropy: amount of disorder in a system Enzyme: protein that serves as a biological catalyst changing the rate of a chemical reaction without itself being changed into a different molecule in the process Enzyme Catalysis: lowers activation energy Exergonic reaction: reactions that yield products that are rich in potential energy. Energy is absorbed form the surroundings as the reaction. Energy is stored in the covalent bonds of the product molecules. Facilitated diffusion: Use of specific transport proteins to move substances down the concentration gradient. Type of passive transport, does not require energy. Rate depends on number of transport proteins. 1st law of Thermodynamics: Energy cannot be created or destroyed, only converted. Glycocalyx: extracellular polymeric material (glycoprotein)[1] produced by some bacteria, epithelia and other cells. The slime on the outside of a fish is considered a glycocalyx Golgi apparatus: an organelle in eukaryotic cells consisting of stacks of membranous sacs that modify store and ship products of the endoplasmic reticulum. Spontaneous reactions: no input of net energy, release of energy. Hypertonic: a solution with a higher solute concentration than the cell Hypotonic: a solution with a solute concentration lower than that of the cell. Inhibitor: stop the binding of a substrate, competitively or noncompetitively, or through feedback-products. Isotonic: The solute concentration of a cell and the isotonic environment are equal. Light microscope: passes visible light through a specimen. Glass bends light to magnify image, living organism. 1000 times Lipid bilayer: fat molecules, hydrophilic heads face outward, exposed to water on both sides of the membrane. Hydrophilic heads point in, shielded from water. Selectively permeable polar or not. Lysosomes: contain digestive( hydrolytic) enzymes enclosed in a sack, break down things, recycling centers, damaged cells, destroys cells. Micrometer: 10-6 of a meter Microtubules: straight hollow tubes composed of globular proteins =called tubulins. Elongate by adding subunits consisting of tubulin pairs. Readily disassembled, provide rigidity and shape. Anchorage for organelles and as tracks for organelle movement within a cytoplasm. Mitochondria: Organelles that carry out cellular respiration in nearly al eukaryotic cells, convert the chemical energy of foods to chemical energy ATP: Mitochondrial density: The increase in mitochondrial density is associated with an increase in the duration one can perform endurance exercise and the ability to spare total body glycogen stores (Fittz et al. , 1975). Generally, more lipids are used to generate ATP as a result of the increased mitochondrial density in response to exercise Nucleolus (nucleoli): Building blocks of ribosomes and RBA messenger ribosomes to amino acid sequences in proteins. Oxidation (catalase): oxygen and other molecules, hydrogen peroxide is broken down with a catalase to create water and oxygen. Passive transport: the diffusion of a substance across a biological membrane. Oxygen, co2 in lungs. No energy needed. Peroxisomes: These are tiny circular membrane bound organelles containing a crystal core of enzymes (such as urate oxidase, peroxidase, D- amino oxidase and catalase, example- liver cells and kidney cells). These enzymes are required by peroxisomes in detoxification activity, i. . , in the metabolism or production of mitochondrial or cytosolic reactions. Peroxisomes are also related with beta- oxidation of fatty acids and thermogenesis like the mitochondria and also in degradation of the amino acids. Phagocytosis: â€Å"cellular eating: pinocytosis â€Å"cell drinking† Plasma membrane: individual proteins and phospholipid molecules can drift fluid. Tails in phospholipid, double bonds in unsaturated fatty acid tales-temperature. Surface has carbohydrates bonded to proteins and lipids in membrane. Cell identification, distinguish cells. Plasmodesmata: channels between adjacent plant cells, circulatory and communication system connecting the cell sin plant tissues. Receptor mediated endocytosis: highly specific, plasma membrane indents to form put lined with receptors that puck up particular molecule from surroundings, pinch to form vesicle. Ribosomes: cell organelle consisting of RNA and protein organized into two subunits and functioning as the site of protein synthesis in the cytoplasm. Scanning electron microscope: study detailed architecture of cell surfaces; surface hit with electrons deflects into device to video screen-three dimensional. Sugar vs pasta 8 micrometers Smoother er: network of interconnected tubules-synthesis of lipid, process drugs, detox enzymes-build resistance, stores calcium ions for contraction. Sodium potassium pump: sodium binds to pump, becomes phosphorylated cost of ATp conforms, translocate sodium ions across membrane, low affinity for sodium ions, diffuse. New conforms high affinity for potassium- bound dissociated and reforms to original formation. Transmission electron microscope: used to study the details of internal cell structure-laced with gold, electron beam electromagnets as lenses, bends beam magnify and focus. In the mitochondrial matrix in the mitochondria, cristae increase surface area- better atp production compartmentalization. Light, sun All in eukaryotic cells Ribosomes and centrioles