building blocks like cells. The cell theory is one of the basic theories of Biology. 2. Are there living beings without cells? Viruses are considered the only living beings that do not have cells. Viruses are constituted by genetic material (DNA or RNA) enwrapped by a protein capsule. They do not have membranes and cell organelles nor do they have self-metabolism. 3. In 1665 Robert Hooke‚ an English scientist‚ published his book Micrographia‚ in which he described that pieces of cork viewed under
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specifically‚ also known as complementary pairing‚ Adenine (A) with Thymine (T)‚ and Guanine (G) with Cytosine (C) by two and three hydrogen bonds‚ respectively. DNA is a long polymer of nucleotides (a polynucleotide) that transfers the information to RNA (mRNA) that in turn controls the sequence of amino acid residues in proteins‚ using the genetic code. James Watson and Francis Crick proposed the DNA double helix structure in 1953 and shared the the Noble Prize in 1962 with Maurice Wilkins. Models
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β-lactams e.g. penicillin 2. Inhibition of synthesis or damage to cytoplasmic membrane * Polymyxins and daptomycin 3. Modification in synthesis or metabolism of nucleic acids * Quinolones (inhibit DNA gyrase)‚ Rifampin (inhibits RNA polymerase) 4. Inhibition or modification of protein synthesis * Aminoglycosides‚ tetracyclines‚ etc. – Inhibit 5. Modification in energy
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separates the contents of the nucleus from the cytoplasm‚ all in all keeping the DNA safe and intact. The nuclear envelope regulates the flow of substances into and out of the nucleus. The NUCLEOLUS is an important structure found within the nucleus. The RNA‚ which will be made into ribosomes is synthesised in the nucleolus. The ribosomes move out of the nucleus to help with protein synthesis. The ROUGH EDOPLASMIC RETICULUM looks rather “pebbeled” through a microscope because of the ribosome’s that are
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Notes: Anatomy & Physiology 1. Cells A cell is the basic‚ living‚ structural‚ and functional unit of the body. Cytology: the study of cells A generalized view of the cell 3 main parts of the cell: Plasma membrane‚ cytoplasm and nucleus. * Plasma (cell) membrane: * Outer‚ limiting membrane separating the cell `s internal components from the extracellular materials and external environment. * Cytoplasm (formed or molded): * Consist of all the cellular contents between
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nucleoside linked to a phosphate group. Nucleotides form the basic structural unit of nucleic acids such as DNA. Complementary bases Guanine is the complementary base of cytosine‚ and adenine is the complementary base of thymine in DNA and of uracil in RNA. Double helix A pair of parallel helices intertwined about a common axis‚ especially that in the structure of the DNA molecule. EXERCISE 1 –DNA structure Which carbon atom (position) in the sugar forms a covalent bond with the nitrogen base? The
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membrane is infolded many times‚ forming a series of projections. The mitochondrion converts the energy stored in glucose. nuclear membrane - the membrane that surrounds the nucleus. nucleolus - an organelle within the nucleus - it is where ribosomal RNA is produced. Some cells have more than one nucleolus. nucleus - spherical body containing many organelles‚ including the nucleolus. The nucleus controls many of the functions of the cell and contains DNA. The nucleus is surrounded by the nuclear
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photosynthesis conversion of CO2 to organic compounds radically changed Earth by producing A) sugar. B) cellulose. -C) O2. D) H2. 8. RNA is believed to have been the initial genetic system because it can A) form a stable double helix with a complementary nucleic acid strand. -B) catalyze the polymerization of nucleotides into another RNA strand. C) form ribosomes. D) transfer amino acids to ribosomes. 9. The initial importance of a
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repressor domain covering the RNA binding and helicase domains. RIG-I recognizes PAMPs based on length of RNA‚ presence of 5’ cap‚ and sequence composition. RNA with a 5’ cap does not activate RIG-I signaling nor does RNA lacking exposed 5’ triphosphates (5’ppp) or 5’ diphosphates (5’pp). The ideal RIG-I PAMP is dsRNA that is less than 300 base pairs with a 5’ppp cap. Once RIG-I recognizes PAMP RNA it hydrolyzes ATP and opens the RNA binding domain for association with PAMP RNA. This also releases the
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terrestrial and aquatic environments. Do not have a rigid cell wall. f. Multicellular paracites (worms) – Live at the expense of a host 4.) List and describe the 3 types of non-living infectious agents g. Viruses – Nucleic acid 9DNA or RNA) surrounded by a protein coat. Multiply by using the machinery and nutrients of living cells. h. Viroids – Consist of only a single‚ short piece of ribonucleic acid. Like viruses‚ they multiply only inside cells. They cause a number of diseases
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