Question

24. Which of the following mechanisms produces the most cells for tissue growth from stem cells? a. The division of the stem cells themselves. b. The division of fully differentiated cells. C. The division of transit amplifying cells. d. The division of stromal/mesenchymal cells. 25. Which of the following would most likely promote cancer if it had a hyperactive mutation? a. E-Cadherin b. Cyclin D c. p27 d. Weet kinase 26. Snakes and lizards each have vertebrae and ribs. Which of the following possibilities would best explain why snakes lack legs? Lack of a specific Hox gene's activity a. b. Lack of lateral inhibition c. Lack of Bicoid gene activity d. Lack of inner cell mass 27. After isolating embryonic stem cells from the inner cell mass, you place them in a culture dish. Your goal is to continue growing them as embryonic stem cells. To accomplish this goal, what factors would you immediately need to add to the culture media in the dish? a. Factors for transit amplification b. Steroid hormones c. The factors Oct3/4, Sox2, Myc, and Kif4 d. None of the above 28. Which of the following statements is correct? a. "In humans, stem cells are only important for embryogenesis." b. "Auditory hair cells are mesenchymal." c. "Cells that grow rapidly, such as skin cells, have no molecular turnover." d. "Unlike female sheep, male sheep are not required in the reproductive cloning of sheep." 29. The different effects of acetylcholine on heart muscle cells, skeletal muscle cells, and salivary gland cells are explained by which the following differences in signalling? different forms of acetylcholine ii. different receptors for the same acetylcholine molecule i. different signalling pathways downstream of the same acetylcholine receptor i. a. i, ii, and i b. i and i only c. i and i only d. i and i only

Answer 1

Answers

24. a

25. b

26. c

27. c

28. d

29. c

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