Why is embryonic stem cell research controversial? a. it requires the destruction of embryos to use the stem cells in research. b. it forces a mandate for all employees to submit to approval of stem cell research c. it reduces the overall potency of the cells. d. it causes birth defects in the embryos that have stem cells extracted.

Option A, It requires the destruction of embryos to use the stem cells in research.

Explanation:

In embryonic stem cell research, the stem cells are obtained from the blastula stage of embryo which causes its destruction. Embryo duting the blastula stage consists of two types of cells a) trophoblastic cell and b) inner cell mass. This inner cell mass contains the embryonic stem cell which is responsible for developing all the cells of the body and hence once this inner cell mass is destroyed no new cell is produced in the body and thus the embryo dies.

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

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a chair, a bed, and a toothbrush

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