Bioaccumulation is the accumulation of substances, such as pesticides, or other chemicals in an organism
        
             
        
        
        
Answer: I don't really understand what you're asking, but arthropods have 8 legs.
 
        
                    
             
        
        
        
Solution:
Rbc, wbc, and platelets all constitute what part of plasma in the whole blood.
Thus this the required answer.
 
        
             
        
        
        
Variations can be genetic or environmental, the traits are passed from one generation to other generation of snail is from from both parents to offspring and through the environment.
The correct answer is C.
Explanation:
Genetic variation in an organism is passed to the offspring by its parents.
environmental variation is the the result of different environment with which individual adapt.
Natural selection is a process in which a suitable trait which is well adapted to the environment is passed on tho future generations.
Genetic variation is the change in DNA or gene of the individual trait. The tree snails having different pattern in their shells is due to the habitat they are living in. 
The snails which have well adapted to the environment are able to reproduce and pass on the traits to their progeny. The variation is due to the traits passed from parents through the environment also.
 
        
             
        
        
        
Answer:
either of two masses of gray matter lying between the cerebral hemispheres on either side of the third ventricle, relaying sensory information and acting as a center for pain perception.
Explanation: