Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 1495
TLS Online TPP Program

#Question id: 1520

Following statements are regarding to enzymatic processing of benzo(a)pyrene to a more potent mutagen and carcinogen.

A. Liver enzymes, particularly P-450 enzymes, modify benzo(a)pyrene in a series of reactions, producing 7,8-diol-9,10-epoxide, a highly potent mutagenic species that reacts with DNA primarily at the N2 atom of a guanine base.

B. The adduct, (+)-trans-anti-B(a)P-N2-dG, causes polymerase to insert an A rather than a C opposite the modified G base. Next time the DNA is replicated, a T will be inserted opposite the A, and the mutation will be complete.

C. Potent mutagen majorly causes conversion of guanine (G) to thymine (T) bases, a transition mutation.

D. When this potent mutagen applied to cultured bronchial epithelial cells, activated benzo(a)pyrene induces many mutations, including activating mutations at codons 175, 248, and 273 of the p53 gene.

Which of the following statements are correct?

#Unit 4. Cell Communication and Cell Signaling

  1. A, B and D

  2. A and B

  3. B, C and D

  4. B only

More Questions
TLS Online TPP Program

#Question id: 12278

#Unit 10. Ecological Principles

In many plant and animal communities that are found on islands, the number of species (S) changes with the area (A) of the island as follows: S = cAz, where 0 <z < 1 and c>0. Which of the following graphs best represents such a species-area relationship?
TLS Online TPP Program

#Question id: 15603

#Unit 12. Applied Biology

Novel antibiotic can be made by
TLS Online TPP Program

#Question id: 7260

#Unit 5. Developmental Biology

There are maternally-determined variations along the animal-vegetal axis that are necessary for normal development in sea urchin. Which of the following statements about regulation in sea urchin embryos is consistent with that fact?
TLS Online TPP Program

#Question id: 20271

#Unit 7. System Physiology – Animal

Nephrogenic diabetes insipidus is treated with thiazide diuretics. The usefulness of thiazide diuretics in treating nephrogenic diabetes insipidus is explained as follows:
a. Thiazide diuretics inhibit Na+ reabsorption in the early distal tubule. By preventing dilution of the urine at that site, the final, excreted urine is less dilute.
b. Thiazide diuretics decrease glomerular filtration rate; because less water is filtered, less water is excreted.
c. Thiazide diuretics, by increasing Na+ excretion, can cause a secondary ECF volume contraction.
Which one of the following combination of above statements is correct?
TLS Online TPP Program

#Question id: 34087

#Unit 3. Fundamental Processes

A DNA containing which an origin of replication undergoing to initiation of replication and further, is digested with restriction endonuclease. Which shape of DNA segment can be found after digestion followed electrophoresis.
A. Y Shape B. Bubble shape C. bubble-to-Y-arc D. Circular