Answer: a. adaptation
Explanation:
Sensory adaptation can be define as the reduction in sensitivity to a stimulus after a constant exposure to the stimulus. When the awareness and sensitivity towards the constant stimulus reduces, then the attention of the receives diverts to another stimulus present in the environment around it.
The given situation demonstrates the sensory adaptation this is because of the fact that Sariah developed the sensory adaptation towards the constant stimulus that is chirping. Now her attention diverts and she was able to talk to her friends, and she lost awareness of chirping although it was still there.
If the Na+ voltage-gated channels in a muscle cell open, the Na (sodium) ions rush inside the muscle cell and makes the cell more positive as Na ions carry positive charge on it. Due to the entry of positively charged ions inside the cell, the cell becomes less negative and more positive. This is called depolarization of cell.
