why are we not sensitive to small decreases in PO2 but we are too PCO2?

You stimulated the cell with a ligand and analyzed the response. Upon ligand treatment, the cell increased the expression of gene α and decreased expression of gene β. When you inhibit cyclic AMP production by treating the cell with an inhibitor of Adenylyl cyclase, the increased expression of gene α was not observed but the decrease gene β expression was still observed. a) What you can expect for gene α regulation by this ligand? What signaling mechanism could be used? b) To determine how gene β is regulated by the ligand via what signaling mechanism, provide your hypothesis and indicate a potential experiment that you can perform to test that.

Many organisms have a class of genes called ' heat shock proteins.' These genes are expressed at high levels when cells are exposed to high temperatures. once they are transcribed and translated, they help stabilize other proteins in the cell to protect them form the high temperature. What kind of response to the enviornment is the elevated expression of heat-shock proteins? - mutational response - direct response - gene-mediated response

1. ALT is not used as a hepatocellular damage marker in cattle. Explain why.

Serotonin is a neurotransmitter that is a small, soluble molecule. P11 (a small protein) is required for transport of serotonin receptors to the cell surface. Assume for this problem that p11 affects transport of serotonin receptors only, and that it does not affect transport of any other proteins (a simplification). Depressed people seem to have low levels of p11; treatments that improve mood increase the expression of the p11 gene. NSAIDs (aspirin, ibuprofen, etc.) seem to decrease expression of p11. SSRIs (selective serotonin reuptake inhibitors) decrease re-uptake of serotonin at synapses. Some depressed patients are helped by SSRIs, but some are not.  Explain both parts of B.  B-1. The results indicate that depression can be caused by levels of serotonin receptors that are (higher than normal) (lower than normal) (neither – no evidence here for any effect on depression) (higher or lower but can't tell which).    B-2. If a depressed person does not respond to SSRIs, the person…

Mutation in the fibroblast growth factor receptor (FGFR) gene results in achondroplasia (dwarfism), which is a dominant condition caused by a single base substitution (GGG>AGG) that changes the amino acid glycine at position 480 to arginine (G480R) in the FGFR protein. FGFR is normally active when FGF binds to it, but the mutant FGFR is always on to stimulate signaling that inhibits excessive bone growth. How can gene therapy be used to treat achondroplasia? Select all that apply. RNAi that knocks down the mutant FGFR expression Adeno-associated viral (AAV) vector that carries the wild-type FGFR Retroviral vector that carries the wild-type FGFR CRISPR with the wild-type FGFR donor DNA

The cell enters g1 and cyclin D binds with CDK4/6  Increases in cyclin D expression prevent p21/p27 from inhibiting cyclin E/CDK2 Rb is hypo-phosphorylated E2F is no longer repressed and induces expression of E2F and cyclin E The cell enters S phase and cyclin A binds to CDK2  cyclin A binds to CDC 2 > Cell enters G2 and cyclin B binds CDC 2  Cell enters M phase and proliferates   Put these in the correct order from 1-8

At any given time, intestinal crypts of mice com-prise about 15 stem cells and 10 Paneth cells. After celldivision, which occurs about once a day, the daughtercells remain stem cells only if they maintain contact with aPaneth cell. This constant competition for Paneth-cell con-tact raises the possibility that crypts might become mono-clonal over time; that is, the crypt cells at one point in timemight derive from only 1 of the 15 stem cells that existedat some earlier time. To test this possibility, you use theso-called confetti marker that upon activation expressesany one of three fluorescent proteins in the stem cells ofthe crypt. You then examine crypts at various times todetermine whether they contain cells with multiple colorsor only one color (Figure Q22–1). Do the crypts becomemonoclonal over time or not? How can you tell?