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.
The answer is A because I’m in advanced classsss!!!
Hello, this is related to the plans concentration of proteins.
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Answer:
DNA packaging contributes to the compaction of the genetic material into cells that are many times smaller and also regulates gene expression and cell replication in living systems.
Explanation:
DNA is a fundamental molecule that contains instructions that make each organism unique. Each chromosome is composed of a very long linear DNA molecule associated with histone proteins that compact the genetic material, which is known as DNA packaging. Transcription and replication require that both strands of the DNA separate. Nonetheless, during DNA packaging, nucleosomes and the folding into chromatin fibers ensure chromosomal DNA is correctly packaged inside smaller nuclei. In consequence, DNA packaging not only enables the compaction of long linear DNA into the cells but also is involved in key biological processes such as gene regulation (transcription) and cell replication.
