When early embryo are releasing chemicals to nearby cells to elicit protein production in the activated neighboring cells. What is the primary function of the signaling molecule? a. facilitating cell death
b. initiating gene translation
c. regulating gene expression
d. stimulating cell division

c. regulating gene expression  

Explanation:

During development, early embryo cells release different ligand molecules that bind to specific receptors on the surface of nearby cells, thereby triggering signaling pathways involved in cell differentiation and development. These signaling events have been associated with the activation of transcription factors located in the cytoplasm which are then translocated into the nucleus where they activate the transcription of target genes. For example, sonic hedgehog (SHH) is a peptide hormone that plays roles during animal development. SHH is secreted by epithelial cells to activate transcription factors in nearby cells involved in several developmental processes.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.