NUSCTX 11, Midterm 1 - UC Berkeley UPDATED ACTUAL
Questions and CORRECT Answers
, What might occur to increase the toxicity of lipophilic Bioaccumulation and Phase I
chemicals?
What could be a specific way that toxicity from an oil spill Absorbs and bioaccumulates in fat, and can be metabolized into carcinogens.
is most harmful to fish?
If a certain substance causes "DNA adducts" which Measure Phase II enzymes and hypothesize that these enzymes are inhibited
experiments could you try to detect it?
Show that the chemical is a mimic for other nucleotides in DNA replication
Measure chemical metabolites in milk in female animals.
What is true about biotransformation? It is a 2-phase process
It can decrease toxicity
It can increase toxicity, it makes compounds more hydrophilic (water soluble)
What are factors in calculating toxicant risk? Exposure
Absorption
Site of Action
Biological factors that determine toxicity? Absorption
Metabolism
Lipophilic character
Distribution (lymph system)
Circulatory path of lymph Route to fast entry into lungs and blood
Circulatory path of bile duct Breaks down lipophilic chemicals, enterohepatic circulation
Circulatory path of portal vein Routes for metabolism by CYP in liver (gut to liver)
TD Toxic Dose
LD Lethal Dose
ED Effective Dose
Margin of Safety LD1/ED99
Possible sites of action for xenobiotics Fat
DNA
Brain
Heart
Proteins
Tissue and cells
What might occur to reduce toxicity of activated Phase II
lipophilic chemicals Antioxidant to reduce free radicals
Questions and CORRECT Answers
, What might occur to increase the toxicity of lipophilic Bioaccumulation and Phase I
chemicals?
What could be a specific way that toxicity from an oil spill Absorbs and bioaccumulates in fat, and can be metabolized into carcinogens.
is most harmful to fish?
If a certain substance causes "DNA adducts" which Measure Phase II enzymes and hypothesize that these enzymes are inhibited
experiments could you try to detect it?
Show that the chemical is a mimic for other nucleotides in DNA replication
Measure chemical metabolites in milk in female animals.
What is true about biotransformation? It is a 2-phase process
It can decrease toxicity
It can increase toxicity, it makes compounds more hydrophilic (water soluble)
What are factors in calculating toxicant risk? Exposure
Absorption
Site of Action
Biological factors that determine toxicity? Absorption
Metabolism
Lipophilic character
Distribution (lymph system)
Circulatory path of lymph Route to fast entry into lungs and blood
Circulatory path of bile duct Breaks down lipophilic chemicals, enterohepatic circulation
Circulatory path of portal vein Routes for metabolism by CYP in liver (gut to liver)
TD Toxic Dose
LD Lethal Dose
ED Effective Dose
Margin of Safety LD1/ED99
Possible sites of action for xenobiotics Fat
DNA
Brain
Heart
Proteins
Tissue and cells
What might occur to reduce toxicity of activated Phase II
lipophilic chemicals Antioxidant to reduce free radicals
