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
Answer:
C. Oceans are carbon sinks because they store more carbon than they emit.
Explanation:
Oceans are carbon sinks because they store more carbon than they emit. Most of the carbon is produced in the respiration process as well as burning of fossil fuels. This carbon moves to the atmosphere and dissolved into the ocean which is required by the vegetation of ocean. Due to this carbon, vegetation produced more food for the organisms. About 25% of all CO2 emissions are absorbed by the ocean. Source is the part of a plant where materials are produced e.g. leaves whereas Sink refers to the part of the plant where the substrate can be stored e.g. roots or stem for starch.
A decomposer it breaks down food that is decaying to only leave the bone of nothing any decaying living object is getting decomposed by mold.