trees do not fix N2 from air they fix oxygen with the help of N2 fixing bacteria . so trees do not fix N2
Without external and internal stimuli, your body would not be able to maintain homeostasis. Homeostasisis a property of systems that regulates their internal environment (blood levels, temperature, nutrient levels, etc.) and tends to maintain a stable, constant condition despite changing external conditions.
The correct answer is phosphorylation. When an ADP (Adenine Diphosphate) molecule gains a phosphate, it becomes an (Adenine Triphosphate) molecule. This process is called a phosphorylation. Phosphorylation and its counterpart dephosphorylation change many proteins in terms of its functions and activities.
These are the thykloid and the stroma