For the answer to the question above, the answer is "Systemic Acquired Resistance''.
<span>it is a whole-plant resistance response and it occurs by following an earlier localized exposure to a pathogen. It is analogous to the innate immune system that can be found in the animals, and there is also an evidence that SAR in plants and innate immunity in the animals may be evolutionarily conserved.</span>
An identical twin I think
If the inner lining of the air sacs neither thin nor highly vascularized, then it can be inferred that AIR SACS ARE CANNOT BE THE SITES OF GASEOUS EXCHANGE BETWEEN AIR AND BLOOD. Air sacs are generally lined with mucus and surrounded with blood capillaries.
In case of birds, air sacs play an important role in respiratory system.
Answer:
1. Ask a question
2. Make a hypothesis
3. Conduct experiment
4. Make observations and record them
5. draw conclusions
6. write a conclusion
Explanation:
