Answer:
I believe the answer is A
Explanation:
The Sun is located in the Orion Arm
Answer:
Explanation:
While passing through renal tubules, water and a lot of other substances are reabsorbed making filtrate concentrated. This also gradually results in an increase in the concentration of urea as it is not reabsorbed like water or glucose. Some substances like K+, H+ are also secreted (not urine).
Answer:
The answer is when the cell express different genes.
Explanation:
Cell differentiation is the process when a cell is changed from one cell type to an other and brings more complexity to the system. A cell before differentiation possess all the genes however their expression in turned off. When some external or internal factors trigger the gene expression it starts the cell differentiation. A multicellular organism undergoes several rounds of cell differentiation during its development. Although cell differentiation changes the size, shape and metabolic activity but the genetic makeup or DNA is never changed during cell differentiation.
