<u>Serial monogamy </u>is the answer.
In definition, monogamy is having only one partner; one man and one woman but serial monogamy is having one partner at a certain length of time which in this case defines the asked question.
Other polygamy is the behavior where one lover has multiple partners altogether.
When something needs to be transported against its concentration gradient, or a molecule is too big to simply diffuse through a membrane, active transport has to be used. So active transport requires energy (ATP).
Examples:
1. Antiport pumps: transport one substance in one direction while transporting another substance the other way. An example of this is the sodium-potassium pump.
2. Symport pumps - uses a substance that wants to move from an area of high concentration to low concentration and carries another substance against its concentration gradient. An example of this is the sodium-glucose transport protein
3. Endocytosis - large amounts of extra cellular fluid can be taken into a cell - needs ATP to bind proteins in the cell membrane and causes them to change their shape...which eventually causes the surrounding of the fluid to be brought in (a vesicle).
4.exocytosis - opposite of above
Adjustment knobs are used to focus light in a light microscope
Myelin greatly speeds up action potential conduction because of exactly that reason: myelin acts as an electrical insulator! Myelin sheath reduces membrane capacitance and increases membrane resistance in the inter-node intervals, thus allowing a fast, saltatory movement of action potentials from node to node.
Hope this helps
