Biochemistry Multiple Choice Questions on “Regulation of Transcription by Steroid Hormones”.
1. How do steroid hormones produce their effects in cells?
A. By activating key enzymes in metabolic pathway
B. By binding to intracellular receptors and promoting transcription of specific genes
C. By promoting the degradation of specific m-RNAs
D. By activating translation of certain m-RNAs
Answer: B
Clarification: Steroid hormones produce their effects in cells by binding to intracellular receptors and promoting transcription of specific genes.
2. Which is an example of a positive regulator?
A. CAP
B. Lac 1 gene
C. Trp operon
D. Met operon
Answer: A
Clarification: Lac 1 gene, Trp operon and Met operon are negative regulators.
3. Which is an example of negative regulator?
A. CAP
B. Lac 1 gene
C. Nuclear receptors
D. Phosphorylated STAT proteins
Answer: B
Clarification: CAP, Nuclear receptors and Phosphorylated STAT proteins are positive regulators.
4. Steroid regulatory proteins mediate the act by binding at ___________
A. Zinc finger motif
B. Leucine zipper motif
C. Helix turn helix motif
D. Histone helix motif
Answer: A
Clarification: Steroid regulatory proteins mediate the act by binding at zinc finger motif.
5. Which out of the following statements is true about gene regulation in bacteria?
A. Repressor protein blocks transcription by binding to operator sequence
B. Activator proteins bind near promoters and increase the efficiency of transcription
C. Enhancers commonly regulate transcription
D. Genes with related functions are often grouped together and have a single start codon
Answer: A
Clarification: A repressor binds at operator element and regulates transcription negatively.
6. Steroid hormones receptor binds to _____________
A. Hormone response elements in m-RNA
B. Hormone response elements in DNA
C. Hormone response elements in proteins
D. Ribosomes to stimulate translation
Answer: B
Clarification: Hormone response elements are short sequence of DNA where steroid hormone receptors bind.
7. Mode of action of steroid hormones involve ______________
A. Stimulation of DNA replication
B. Stimulation of m-RNA transcription
C. Inhibition of protein synthesis
D. Secondary messenger
Answer: B
Clarification: Steroid hormones involve in the stimulation of m-RNA transcription, affecting the gene expression.
8. What is the drug antagonist of estrogen?
A. Tanoxifen
B. Metformin
C. Glucophage
D. Victoza
Answer: A
Clarification: Tanoxifen is an antagonist of estrogen.
9. Which drug is used to terminate early pregnancies?
A. RU486
B. Metformin
C. Glucophage
D. Victoza
Answer: A
Clarification: Metformin, Glucophage and victoza are the drugs to cure diabetes.
10. Plasma membrane protein predicted to have seen 7 transmembrane helices segment binds __________
A. Progesterone
B. Thyroid stimulating hormone
C. Insulin
D. Follicle stimulating hormone
Answer: A
Clarification: Progesterone hormone is a steroid hormone, can diffuse through cell membranes.
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