Why the Calcium ions are flowing into the cell from the extracellular matrix (outside of the cell)

The serengeti plains are part of the african savanna ecosystem and are home to a variety of different species of plants and animals. the serengeti plains experience a seven-month period of seasonal drought each year, during which the ecosystem receives only four inches of rain and the availability of some resources becomes very scarce. which type of limiting factors does the seasonal drought in the serengeti plains affect?

Why does controlling transcription affect prokaryotic gene expression?

Which sets of mrna codons could genetically come for a protein with the following amino acid composition