The spinal cord is the answer
        
             
        
        
        
1-Charles Darwin
2-Alfred Russel Wallace
Explanation:
are jointly credited with coming up with the theory of evolution by natural selection, having co-published on it in 1858. Darwin has generally overshadowed Wallace since the publication of On the Origin of Species in 1859, however.
 
        
             
        
        
        
A: Homeostasis
Reason: cell membrane has nothing to do with question and C and D are terms for sugars
        
                    
             
        
        
        
Grade II Concussion
The brain is made of soft tissue. It's cushioned by spinal fluid and encased in the protective shell of the skull. When you sustain a concussion, the impact can jolt your brain. Sometimes, it literally causes it to move around in your head. Traumatic brain injuries can cause bruising, damage to the blood vessels, and injury to the nerves.