16. Alternative RNA splicing _____.
(A) can allow the production of proteins of different sizes and functions from a single gene
(B)can allow the production of similar proteins from different RNAs
(C) is a mechanism for increasing the rate of transcription
(D) is due to the presence or absence of particular ribosomal proteins

12. A C4 plant minimizes photorespiration by (A) stomata that are only opened at night, storing carbon dioxide in malate, and releasing carbon dioxide during the day. (B)having the light reactions and carbon reactions occur in different cells, so oxygen does not come into contact with rubisco. (C) having the light reactions and carbon reactions occur in different cells, so carbon dioxide does not come into contact with rubisco. (D) stomata that are only opened at night, storing oxygen in malate, and releasing oxygen during the day.

複選題13. Which of the following statements about eukaryotic cell is true? (A) If a cell contains 20 chromosomes in G1 phase, it will contain 40 chromosomes at the end of S phase. (B)During prometaphase, the sister chromatids organize into a single row in the center of the cell. (C) One major difference between metaphase I and metaphase II is the presence or absence of bivalents. (D) Sister chromatids are produced during mitosis. (E)If environmental conditions are favorable during the G1 phase, G1 cyclins are degraded causing the cell to prepare to replicate its DNA.

14. In goats, the gene for coat color is on an autosome and light brown color is dominant to black. A light brown male is mated to a black female, producing a black kid (baby goat). If they produce another kid, could it be light brown? If so, what are the chances of it being light brown? (A) No, since the black allele is present all offspring will be black. (B)Yes, 100% since the first kid was black the next one has to be light brown. (C) Yes, 75% since light brown is dominant. (D) Yes, 50% as the male must be heterozygous for color.

15. Which of the following is not accurate regarding the Bicoid protein? (A) Bicoid protein is a molecule that determines fly tail. (B)A homozygote with bicoid gene mutation can develop normally if its mother is normal. (C) Bicoid gene is transcribed by nurse cells during oogenesis. (D) Bicoid protein activates genes when it reaches a concentration threshold.

17. Which of the following is the first event to take place in translation in eukaryotes? (A) Base pairing of activated methionine-tRNA to AUG of the messenger RNA (B)Covalent bonding between the first two amino acids (C) The small subunit of the ribosome recognizes and attaches to the 5' cap of mRNA (D) Binding of the larger ribosomal subunit to smaller ribosomal subunits

複選題18. Which of the following statements is true? (A) As part of the transcriptional unit, regulatory sequences are the sites where RNA polymerase and transcription factors bind to regulate transcription. (B)All enzymes are proteins. (C) tRNA contains the genetic code for producing a polypeptide. (D) The termination of translation occurs when a release factor recognizes the stop codon. (E)A single gene always encodes an enzyme.

19. MicroRNAs (miRNAs) (A) are long RNA molecules. (B)silence the expression of specific mRNAs. (C) are found only in animals. (D) are cut by an enzyme called transcriptase. (E)inhibit the catalytic activity of rRNA

20. Which of the following characters is not unique to Metazoa? (A) Multicellularity (B)Having a nervous system (C) An extracellular matrix made up by collagen (D) Movement by muscle

21. Protists are   not   monophyletic. This means that protists (A) are not all members of the same phylum (B)are all more closely related to each other than they are to any other kind of organisms (C) are not all more closely related to each other than they are to some other organisms (D) are all more closely related to bacteria than they are to other organisms

22. Which of the following statements is not true of the stomata on the leaves of vascular plants? (A) They regulate intake of carbon dioxide needed for photosynthesis. (B)They regulate release of oxygen to the air. (C) They regulate loss of water. (D) They regulate the absorption of light by chlorophyll.