29. Which one of the following is the cancer of epithelial cells?
(A)Sarcoma.
(B) Myeloma.
(C) Leukemia.
(D)Lymphoma.
(E)Carcinoma.

25. Which one of the following is the best characteristic of microRNAs (miRNAs)? (A)MicroRNAs are short RNA molecules that encoded by genome. (B) MicroRNAs can target the genome to suppress gene expression. (C) MicroRNAs can edit the RNA sequence. (D)MicroRNAs can edit DNA sequence. (E)MicroRNAs can edit amino acid sequence of protein.

26. Bacteria are grown in isotopic 15N (heavy) medium and then transferred to 14N (light) medium and allowed to replicate for 2 generations. The DNA is subsequently isolated and centrifuged in a CsCl2 gradient to yield what type of gradient band(s)? (A)One heavy and one half-heavy band. (B) One light and one half-heavy band. (C) One half-heavy (intermediate to heavy and light) band. (D)One heavy band. (E)One light band.

27. Where would one expect to find the most abundant/active telomerase? (A)Male germ cells that give rise to gametes. (B) A nerve cell from a 2-year-old individual. (C) A nerve cell from a 40-year-old individual. (D)Skin cells from a 2-year-old individual. (E)Skin cells from a 60-year-old individual.

28. ______ is a type of physical mutagens could induce thymine dimer mutations. (A)Gamma rays (B) X-rays (C) Microwave (D)Ultraviolet light (E)Ionizing radiation

30. When cancer cells can migrate to other parts of the body, they are always said to be____. (A)benign (B) invasive (C) metastatic (D)oncogenic (E)genetic

31. Humans have __________ different types of autosomes. (A)11 (B) 22 (C) 33 (D)44 (E)46

32. Meiosis I produces ________, and meiosis II produces _______ cells. (A)2 diploid, 2 haploid (B) 2 haploid, 2 haploid (C) 2 diploid, 4 haploid (D)2 haploid, 4 haploid (E)2 somatic, 2 gametic

33. Sister chromatids separate during _________. (A)metaphase of meiosis I (B) metaphase of meiosis II (C) prophase of meiosis I (D)prometaphase of meiosis I (E)anaphase of meiosis II

34. What enzyme does the lacZ gene encode? (A)DNase. (B) Carbonic anhydrase. (C) β-galactosidase. (D)Glucose dehydrogenase. (E)Succinate dehydrogenase.

35. Which one of the following is the best statement about genomic library and cDNA library? (A)A cDNA library is derived from mRNA by using reverse transcriptase. (B) A genomic library is derived from mRNA by using reverse transcriptase. (C) The number of DNA fragment in genomic library is the same to cDNA library. (D)One DNA sequence can generate one cDNA. (E)Most of DNA sequences from cDNA library are longer than that from genomic library.