39. In humans, the phenylalanine hydroxylase gene is 90,000 bases (90 kb) long, yet the mRNA is only 2,400 bases (2.4 kb). What explains this difference?
(A) RNA editing
(B) Code for poly A tail that is removed in mRNA
(C) Loss of stability without a 5’ cap
(D) Removal of exons in the final mRNA
(E) Presence of introns in DNA

35. To prevent irreversible tragedies, the CDC urges the public not to use blood donation as a means of Human immunodeficiency virus (HIV) testing, as there is a period for HIV infection. (A) prophase (B) infectious (C) latency (D) anaphase (E) telophase

36. Which of the following characters is NOT a terrestrial adaptation of plants? (A) Waxy stomata to reduce water loss (B) Vascular tissue in most plants to transport water/sugar within the plant (C) Specialization within the plant with root/shoot (D) Spore/seed for dispersal (E) Flagellated sperm

37. Which of the following genetic changes of K-Ras is detected in over 90% of human pancreatic cancers? (A) Translocation (B) Mutation (C) Promoter methylation (D) Amplification (E) Transposition

38. In the process of human gametogenesis, which cell is haploid? (A) Spermatogonium (B) Primary spermatocyte (C) Primary oocyte (D) Early spermatid (E) Oogonium

40. Which of the following organelles CANNOT be found in animal cells? (A) Lysosome (B) Central vacuole (C) Mitochondrion (D) Peroxisome (E) Centriole

41. Which is NOT a source of genetic variation that makes evolution possible? (A) Oxidative phosphorylation (B) Formation of new alleles (C) Sexual reproduction (D) Altering gene number or position (E) Rapid reproduction

42. Which of the following systems allow arthropods to propel the hemolymph into hemocoel? (A) Closed circulatory system (B) Open circulatory system (C) Respiratory system (D) Reproductive system (E) Digestive system

43. What is the evolutionary sequence that is believed to have given rise to the chloroplasts of land plants? (A) Cyanobacteria → brown algae → land plants (B) Photosynthetic bacteria → brown algae → green algae → land plants (C) Diatoms → green algae → land plants (D) Cyanobacteria → diatoms → green algae → land plants (E) Cyanobacteria → green algae → land plants

44. Which of the following statements about genetic drift is TRUE? (A) Genetic drift is significant in big populations. (B) Genetic drift can cause allele frequencies to change at random. (C) Genetic drift results in increased genetic variation within a population. (D) In very big populations, genetic drift can also cause slightly harmful allele to become fixed. (E) Genetic drift can preserve alleles in a population.

45. Regarding plant organ and its components, which of the following sets is NOT true? (A) Spores vs. sperms (B) Archegonia vs. eggs (C) Antheridia vs. sperms (D) Ovules vs. eggs (E) Seeds vs. embryos