Single bacterial cell can carry multiple plasmids - Normal functioning of bacterial cell is not dependent on genetic information contained in plasmid, but DNA often codes for proteins that are advantageous to cell ANTIBIOTICS Definition of Antibiotic - Antibiotic: medicine that kills or inhibits bacteria Classes of Antibiotics
- Beta-Lactam Antibiotics - EXAMPLES: - Amoxicillin - Ampicillin - Tetracyclines - EXAMPLE: - Doxycycline - Fluoroquinolones - EXAMPLES: - Ciprofloxacin - Levofloxacin - Sulfa Antibiotics - EXAMPLE: - sulfamethoxazole How Each Class Affects Bacteria - Beta-Lactam Antibiotics - Irreversibly inhibits enzymes involved in final steps of cell wall synthesis - Enzyme inhibited by these drugs mediate formation of peptide bridges between adjacent strands of peptidoglycan - Drugs vary in spectrum of activity - Some are more active against Gram +, where others are more active against Gram - Tetracyclines - Reversibly binds to 30S ribosomal subunit, blocking the attachment of tRNA to ribosome and preventing continuation of protein synthesis - Effective against Gram + and Gram - - Fluoroquinolones - Inhibit one or more of a group of enzymes called topoisomerases, which maintain supercoiling of chromosomal DNA within bacterial cells - Inhibition of these enzymes prevent essential cell processes - Active against wide variety of bacteria, including both Gram + and Gram - - Sulfonamides - Inhibit growth of many gram + and Gram - bacteria - Structurally similar to para aminobenzoic acid, substrate in pathway for folic acid biosynthesis - Enzyme that normally binds with PABA preferentially binds with the sulfonamide drugs, resulting in its competitive inhibition - Human cells are not affected by these drugs, because they lack this enzyme
What causes Antibiotic Resistance to Develop in Bacteria - Bacteria are able to evolve and become antibiotic resistant - Mutation can give cell wall, the way proteins are produced - Bacteria grows then divides - Able to share plasmids through transduction, transformation - Plasmids can be exchanged over gene that is resistant to another EAR, SOUND, HEARING General Function of Outer, Middle, Inner Ear - Outer Ear - Funnel and transport sound waves to tympanic membrane which converts into vibrations - Middle Ear - Transmit sound vibrations through ossicles - Inner Ear - Turn sound vibrations into electrical impulse to be sent to brain Which Type of Hearing Loss Would Cochlear Implants Be Used - Sensorineural hearing loss: where cochlear hair cells or auditory nerves are damaged OR electrical information cannot be send to brain correctly - Function of Auditory Nerve, Semicircular Canals - Auditory nerve: transmits electrical impulse of sound to brain - Semicircular canals: three tiny fluid-filled tubes in inner ear that help keep balance Pitch, Amplitude, Frequency, Wavelength
- Pitch: the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone - Frequency: the rate at which a vibration occurs that constitutes a wave; the rate at which something occurs of is repeated over a particular period of time - Wavelength: the distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave Tinnitus -
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