Question

1. Fill in the blanks for the following questions. (2 marks each, 36 marks total) a) The overall uptake of a xenobiotic in an organism from all sources is termed b) The most common type of reaction of a xenobiotic with a target molecule is c) Xenobiotics that bind to receptors and produce a reduced effect compared to the endogenous ligand are called Endocrine disrupting chemicals cause toxicity most commonly by binding to d) receptors. e) During chronic dru g therapy, receptors may become resulting in a reduced pharmacological effect at the same dose. is a term that describes the phenomenon whereby a xenobiotic increases in concentration at each higher trophic level of a food web. Approximately 60% of all pharmaceuticals produce their effects by binding to g) receptors. h) Benzodiazepines cause effectsby activating receptors. i) Xenobiotics that bind to receptors but produce no response are called j) Receptors with no known endogenous ligand are called k) Certain xenobiotics have a chiral carbon in their structure that results in two that often have different toxicological properties. I) The ratio of xenobiotic concentration in an aquatic species (e.g., clam) to the concentration of the same xenobiotic in water is called m) Genetically-based, unexplained responses to xenobiotics are called n) Xenobiotic damage to protein thiol groups can be repaired by o) The single most important index used to describe the efficiency of xenobiotic excretion by an animal is p) Excision repair of damaged DNA is catalyzed by the enzymes and

Answer 1

1. Fill in the blanks for the following questions.(2 marks each, 36 marks total)

a). The overall uptake of a xenobiotic in an organism from all sources is termed - absorption.

b). The most common type of reaction of a xenobiotic with a target molecule is - Non covalent binding (reversible).