By dating the rocks in the ever-changing crust, as well as neighbors such as the moon and visiting meteorites, scientists have calculated that Earth is 4.54 billion years old, with an error range of 50 million years.
Through a cut or an injury where any skin has been broken.
An infection through an animal's bite or sting.(Like the West Nile Virus which spreads though mosquito bite, or Rabies though an infected mammal's bite).
Can be inhaled or consumed and go from the lungs into the other organs causing harm internally.
Answer:
B) All DNA molecules will migrate up the gel toward the positive electrode.
Explanation:
Because the DNA has a negative charge - regardless the size-, all DNA molecules will migrate towards the positive electrode, at the top of the gel. This is due to the Coulomb's physic law "force of the interaction between the charges is attractive if the charges have opposite signs".
Instead of migrate down the gel , the DNA will do migrate up the gel (opposite direction).
both sudden slip on a fault
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.
