Answer is 4. Algae incorporated prokaryotic cells that became chloroplasts, but never acquired mitochondria.
Explanation:
It should be noted , that symbiosis or symbiotic relationship is a type of relationship involving two organisms where, one may benefits while the other suffers or both organisms benefit. Symbiosis, may involve one organism living inside or outside the other.
In a situation, whereby one of the organisms involved lived inside the order , is being referred to as endosymbiosis.
This endosymbiosis has been described as probably a means through which the eukaryotic cells got or developed some organelles like chloroplasts and mitochondria.
The integumentary system is the skin. Skin protects the inner organs from Bactria. Essentially the skin is a wall protecting against the outside world. It doesn't really release anything but is just there for protection.
The electrochemical gradients set up by primary active transport store energy, which can be discharged as the particles move down their slopes or gradients. Secondary active transport utilizes the energy put away in these inclinations or gradients to move different substances against their own gradients.
For instance, we should assume we have a high concentration of sodium particles or ions in the extracellular space. On the off chance that a course or route, for example, a channel or transporter protein is open, sodium particles will descend their concentration gradient and come back to the inside of the cell.
