Your pupil expands in dim light and contracts in bright light.
It is called a cell membrane potential
Lipids are unique because, they are made from one carbon skeleton unlike the other macro molecules groups which are made from smaller building blocks.
With the exception of steroid hormones, lipids are generally hydrophobic. Also lipids are relative small molecules when compare in size with other macromolecules.
Answer:
Actin filaments return to their original positions (does not occur in muscle contraction, according to the sliding filament model).
Explanation:
Answer: base substitutions, deletions and insertions