Answer:
The correct answer is option c. "Tetracycline must be discontinued before beginning the isotretinoin".
Explanation:
Isotretinoin is a medication used to treat cases of severe acne, having dramatic positive effects since the patients start the treatment. However, the use isotretinoin should be monitored by a doctor because it is hard to process and could cause renal side effects. In this case, the patient must discontinue its treatment with tetracycline before start using isotretinoin.
Answer:
Liver phosphorylase a concentration decreases when glucose enters the blood.
The binding of glucose to liver phosphorylase a shifts the equilibrium from the active form
As the concentration of phosphorylase a decreases, the activity of glycogen synthase increases. to the inactive form
Explanation:
Protein phosphatase 1 (PP1) is a phosphatase enzyme known to remove phosphate groups from serine/threonine amino acid residues. PP1 plays diverse biological roles including, among others, cell progression, control of glucose metabolism, muscle contraction, etc. In glucose metabolism, PP1 regulates diverse glycogen metabolizing enzymes (e.g., glycogen synthase, glycogen phosphorylase, etc). In the liver, glycogen phosphorylase catalyzes the rate-limiting step in glycogenolysis by releasing glucose-1-phosphate. Glycogen phosphorylase <em>a</em> is converted (and inactivated) into the <em>b</em> form by PP1, which catalyzes the hydrolysis of the phosphate bond between serine and the phosphoryl group. In the liver, glucose binds in order to inhibit glycogen phosphorylase <em>a</em>, thereby inducing the dissociation and activation of PP1 from glycogen phosphorylase <em>a</em>.
Mutualism. e.g. oxpecker and zebra
commensalism. e.g. remora fish and sharks
parasitism. e.g. tapeworms and cow