Answer:
 cnidarians
Explanation:
Cnidarian is a phylum of organisms that comprises of the simplest forms of multicellular organisms. Examples of cnidarians includes; coral animals, jellyfish, and sea anemones among others.
They are soft-bodied, carnivorous animals that have stinging tentacles arranged in circles around their mouths. They are the simplest animals to have body symmetry and specialized tissue.
All cnidarians are aquatic, mostly marine organisms, and have two body layers that is the ectoderm and endoderm.
 
        
                    
             
        
        
        
Women who take folic acid pills during pregnancy have about half the probability of having a child with autism as compared to other women. Autism is a range of conditions that are characterized by challenges with social skills, repetitive behaviors, speech and non verbal communications, as well as by unique strengths and differences. Folic acid is very important as it helps the body make healthy new cells.
        
             
        
        
        
I think the answer you are looking for is that the stomach is the fourth level of organization. 
        
                    
             
        
        
        
The water would freeze across the surface of the lake, blocking the dissolving of oxygen and nutrients. <span>Water is actually less dense when frozen, which is why ice cubes and ice bergs all float. This is also why you can ice skate on a lake if the ice gets thick enough on the surface. Many organisms that live in freezing lakes have special adaptations which help them survive.</span>
        
                    
             
        
        
        
<span>Mature tRNA has an amino acid binding site at one end and the other end interacts with the mRNA by complementary base pairing due to the presence of an anticodon. An anticodon is a three nucleotide sequence which is complementary to the triplet codon of mRNA which specifies a protein for synthesis.</span>