.Answer:
Option A, fix nitrogen inside nodules on the roots of legumes
Explanation:
Rizhobium bacteria live in symbiotic relationship with roots of leguminous plants such as pulses including alfalfa, soybean etc.
Rhizobium or Bradyrhizobium is a gram negative bacteria that satisfies the nitrogen starvation of host plant.
These bacteria get habitation and nutrition from these leguminous plants and in return they fix the nitrogen into the nodules of the roots. This is a kind of facultative association between soil bacteria rizhobium and legume plants.
Hence, option A is correct
Thus, option A is correct
It is not c or d. I think it is a.
Atom, cell, tissue, organ
The correct answer is a structure that would differentiate the hollow heart into chambers to separate oxygenated blood.
The heart has four chambers: two ventricles and two atria. The right atrium gets oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-deficient blood to the lungs.
The left atrium gets oxygen-enriched blood from the lungs and pumps it to the left ventricle, and the left ventricle pumps the oxygen-enriched blood to the body. The right and left atrium are distinguished by a wall of tissue known as the atrial septum, and the left and right ventricles are separated by the ventricular septum.
