Inner core, outer core, mantle and crust
Organ system is the most complex in organization
<span>A. Accept 3 electrons from another atom in an ionic bond.
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I think the veins absorb the photons because they're located at the top part of a leaf while the stomata that serves as the leaf's lungs are found at the under side.
Every cell of the organism has the same DNA sequence and same genes. However, not all genes are expressed in every single cell at the same time. Only those genes necessary for a specialised function of a specialised cell are expressed in the specialised cell. For example, skin cells have some different proteins than nerve cells. Genes responsible for those "skin proteins" are activated in skin cells and are turned off in nerve cells.
