The placenta is a strange, important and interesting tissue because: a. It is made of many cells that have fused together, and it has many nuclei. b. It is made possible by an env gene from an ancient retrovirus that became integrated into the mammalian genome. c. The same gene that allows retrovirus membranes to fuse with host cell membranes allows fetal trophoblast cells to fuse together and form the placenta. d. All of the above.

The placenta is a strange, important and interesting tissue because: a. It is made of many cells that have fused together, and it has many nuclei. b. It is made possible by an env gene from an ancient retrovirus that became integrated into the mammalian genome. c. The same gene that allows retrovirus membranes to fuse with host cell membranes allows fetal trophoblast cells to fuse together and form the placenta. d. All of the above.

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter18: Animal Reproduction And Development

Section: Chapter Questions

Problem 7RQ: Which of the following gives rise to the skin cells? a. ectoderm b. endoderm c. mesoderm d. none of...

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