Answer:
The correct answer is - D. All rocks were molten in that time period.
Explanation:
The early Precambrian era began 4.6 billion years ago. The formation of eath start from this era with dust and gas. The atmosphere at that time was too hot. It was like hades. The rocks were molten and appear to like an ocean of rocks.
Due to the molten rocks, there are no samples of rock from this area as it was too hot to be formed. There were boiling sulfur and gases were everywhere.
Answer:
Explanation:
The cell membrane separates the cell from the outer environment. The extracellular fluid contains the sodium ions (Na+), chloride ions (Cl-), while intracellular fluid contains potassium (K +) and negative anions.
The potential difference arises when the membrane is selectively permeable to some ions. The resting potential is -70mV.
When the neurons get excited, the sodium ions start to enter by sodium channels.
Now there are more positive ions inside the cell membrane. It disturbs the resting potential i.e. -70mV. This stage is known as depolarization.
When the inside environment of the cell is more positively charged, the potassium ions start to move out of the cell. It goes out by the voltage-gated channels. Thus resting stage is maintained and it is known as repolarization.
But the initial stability of the cell membrane has to be maintained. To restore the resting stage, the sodium ions start to move out of the membrane and potassium ions enter into the cells again. This is an active transport and has done by the Na+ - K+ pump. Here 3 sodium ions move out and 2 potassium ions pumped into the cell through the plasma membrane.
Thus the resting potential regains. The potassium ions come back into the cells against the concentration gradient and ATP provides the energy for this phenomena.
Answer:
Ar
Explanation:
Argon isn't with the metals on the periodic table
