practice_book_biology

17 the tubulin heterodimer depicted above is located

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: lin heterodimer depicted above is located within a protofilament of an intact microtubule. portion of its neighboring To which site is the heterodimer (within the same protofilament) attached? (A) (B) (C) (D) (E) L M N O P GO ON TO THE NEXT PAGE. Unauthorized copying or reuse of any part of this page is illegal. 17 21. An X-linked recessive gene produces red-green color blindness in humans. A woman with normal color vision whose father was color-blind marries a color-blind man. What is the probability that their son will be color-blind? (A) (B) (C) (D) (E) 0 1/4 1/2 3/4 1/1 25. In nerves, vesicles can move the length of an axon at a rate that far exceeds that which would be predicted for simple diffusion. Which of the following models best explains vesicular movement in these cells? (A) Depolymerization of actin microfilaments attached to vesicles pulls the vesicles toward the site of depolymerization. (B) Vesicles are propelled by fluid movement generated by changes in osmotic potential within the cells. (C) Vesicles are moved by alternate contraction and relaxation of actin-myosin “muscle” complexes. (D) Vesicles, by virtue of their net negative charge, are attracted to positively charged regions of the cell. (E) Vesicles are attached to the protein kinesin, which slides along microtubules by an ATPdependent process. 26. Additions or deletions of bases in the nucleotide sequence of a structural gene most often result in (A) an altered sequence of amino acids in the protein that the gene encodes (B) insertion of a new intron into the coding sequence of the gene (C) decreased histone binding (D) decreased excision repair (E) increased levels of mRNA production 27. Radioactive cytosine was added to an actively growing culture of E. coli bacteria. Which of the following would be the result if a cell replicated once in the presence of this radioactive base? (A) One of the daughter cells, but not the other, would have radioactive DNA. (B) Neither of the two daughter cells would have radioactive DNA. (C) Both daughter cells would have radioactive DNA. (D) Radioactive cytosine would pair with nonradioactive adenine during DNA replication. (E) DNA replication would not occur, because two radioactive bases are required for proper pairing. 22. Which of the following is NOT a correct statement about the process of meiosis? (A) Meiosis I separates chromosomes; meiosis II separates chromatids. (B) Synapsis and crossing-over occur during meiosis I. (C) Kinetochores are responsible for aligning chromatids during meiosis I. (D) Karyokinesis occurs before cytokinesis. (E) Segregation of unlinked alleles occurs during meiosis. 23. Endoplasmic reticulum (ER) is the site of all of the following EXCEPT (A) drug detoxification by means of mixedfunction oxidases (B) synthesis of proteins that are secreted from the cell (C) N-linked glycosylation of newly formed polypeptides (D) Ca2+ storage in muscle tissues (E) hydrolytic activities carried out by acid hydrolases 24. Exons of a ge...
View Full Document

This document was uploaded on 03/16/2014 for the course BIO 1434 at UT Arlington.

Ask a homework question - tutors are online