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:
Is made of a lipid trilayer
Explanation:
The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells.
Answer:
D-Vacuole
Explanation:
The vacuole performs many functions such as storing water, nutrients,and wastes and it also plays a major role in the structure of the plant
The early signs of a heart attack occur in 50% of patients that have a heart attack according to the Society of Cardiovascular Patient Care. If the early symptoms are noticed the treatment can be administered to prevent damage to the heart as the most heart damages, 85% occur in the 2 hours following the attack.
