Answer:
The chemical and electrical signals are used by brain for communication,sensation and thought. Brain uses electrical signals from communication.
Answer: Cell membrane
Explanation:
The cell membrane has the ability to transfer the molecules from the exterior of the cell to the interior of the cell.
The cell membrane is semi permeable which means only selected molecules will pass through the cell membrane.
The molecules and substances that are synthesized inside the cell needs to be transported from inside to outside via cell membrane.
Answer:
The roots organ is genereally placed under the soil and may undero variious modifications. The roots are present in plant that help them to absorb water and nutrient from the soil.
Some plant roots contains the bacteria that helps in the conversion of nitrogen into ammonium ions. The plants changes the roots because the rhizobium present in plant roots helps in the conversion of nitrogen so that it can be used by the plants. The Rhizobium produces ammonium (NH4+) ions.