The correct answer is option A. They either match up with a receptor molecule on the surface of the cell or enter the cell through the membrane.
The intercellular signals are the signals, which transfer the signals from one cell to the another and the intracellular signals are those signals, which carries message within the cell.
The intercellular signals may or may not be transferred through the gap junctions. The chemical signals are one of the type of the cell signals. The chemical signalling molecules generally have a receptor on the cells, where these molecules can bind and can be cause the activation of the cell. The chemical signals can also enter into the cells through active transport and facilitated diffusion. So, these type of transports does not go through the Gap junction.
Answer:
i would say 2. and 4.
tides are made by the moon..... but the plates under the Earth's suface causes larger waves.
Explanation:
i know it is not 3. but i'm not sure what 1. is.
I'm sorry i couldn't help more, but i hope this helps you out!
Bromothymol blue is used as an indicator in many laboratory reactions.<span> This is a dye that is considered to be pH sensitive</span>
Answer:A plane's engines are designed to move it forward at high speed. That makes air flow rapidly over the wings, which throw the air down toward the ground, generating an upward force called lift that overcomes the plane's weight and holds it in the sky. ... The wings force the air downward and that pushes the plane upward.