Answer:
Poriferans.
Explanation:
The evolution of the organisms has been occur from the simple organisms and leads to the evolution of the more complex organisms. This complexity arises due to the changing environment of the organisms.
The protozoans are the simplest organisms and all the other animal lineage has been derived from the porifera. The porifera are the cellular organisms that  do not have tissue level of organization and simple physiological system. Later, diverse and complex organisms arise from the porifera.
Thus, the correct answer is option (1).
 
        
             
        
        
        
Answer:
Similarities: both are chemical messengers, both can have (but don't necessarily have) similar structures (made from amino acids), both can be produced by the central nervous system (hypothalamus produces some hormones), certain molecules can act as both hormones and neurotransmitters (example: norepinephrine).
Differences: neurotransmitters are released by neurons across a synaptic gap, have very short distances to travel, and act very quickly on the neighboring cell. Hormones are released by glands and often have to travel longer distances, which means that they are slower-acting. Also, hormones are typically used for regulation (negative feedback) while neurotransmitters are used for stimulation of a neighboring cell.
Explanation:
 
        
             
        
        
        
Answer: The gas of Fire constrains the atoms that make up oxygen in the air. Plants release oxygen, and take in carbon dioxide.
 
        
             
        
        
        
This would be the nucleiod region.