The correct sequence is option (c)
All the living organisms in the world responds to the environmental conditions and that condition could be temperature, pressure, etc. The changes in the environmental conditions are first observed by the cells of the body and then by the tissues and then from tissues it gets transferred to the organ then to organ system and finally the organism responds to the change.
The part of the Human body that is most similar in function to the spongy mesophyll layer in a leaf is A) Alveoli in the lungs.
During normal breathing, the brain is stimulated to breath with increasing acidity as a result of CO2 concentration from basic metabolic processes. The brain is quite selfish and only really wants to maintain it's pH which should be at a range of 7.3-7.45, and will not tolerate any decrease.
In patients who have a chronic respiratory disorder with things like COPD. The brain has become accustomed to excessive acidic content, and is now stimulated by the Hypoxic drive or by low oxygen content.
