In a few short sentences outline Signal Transduction.
Signal Transduction - is the process whereby chemical/physical signal is transmitted through a series of events (cascade), generally phosphorylation via protein kinases. There are three stages to cellular signaling which include: Reception, Transduction, and Response. Reception- is the where the target cell detects a signal molecule (i.e. ligand/androgen) present in the extracellular environment. Transduction- is the conversion of the the signal to a response via a cascade of events. Response- the specific effect from the signal molecule (i.e. apoptosis, cell proliferation) Transduction At each step of of transduction, a enzyme called a kinase will phosphorylate activating the next step in cascade. Though not all of the molecules in the signal transduction pathway are protein, the proteins that are enhances the signal resulting in a larger response.
True or false? If the question is false elaborate why. - Bases have a pH level below 7.
False, pH is a scale from 1 to 14 (1 being acidic ; 14 being basic) used to determine how acidic or basic an aqueous solution is. pH is measured in moles/liter of hydrogen ions present and follows the principal of negative log base 10. With that being said, the difference of one pH unit (i.e. pH 6 to pH 7) is tenfold. Pure water is normally written as H20 however another way to write the formula is HOH... H (positively charged) + OH (negatively charged) = H(+)OH(-) therefore the properties cancel out. An acidic solution has an higher concentration of hydrogen ions (H+) than pure water, while a basic (alkaline) has an higher concentration of Hydroxyl ions (OH-). Therefore, Bases have a pH level of above 7.
List and describe five (3) functions of proteins. Give Examples.
Transport Proteins - Classified as integral transmembrane proteins and function by the passage of small molecules across the cell membrane. Passage of molecules are based on a number of factors including polarity and size just to name a few. Transport proteins can further be classified as channels and carrier proteins. -Serotonin Transporter Antibody - Classified as immunoglobulin and functions by binding to specific foreign substances in the cell. Antibodies are implemented in the naturalization of pathogens (i.e. bacteria and viruses) -IgM (usually first line of defense for infection) Enzymes - Classified as catalyst and functions by accelerating chemical reactions by lowering the activation energy. Enzymatic activity can be influenced by other molecules, such as inhibitors (decrease activity) and activators (increase activity). -alcohol dehydrogenase (primary defense against alcohol)