Answer 
Complex barrier to the flow of substances out of the cells,and restrictions to inflow of unwanted substances into the cells. The hydrophobic and hydrophilic nature of the cell membrane controls the entry of substances from the extracellular medium into the intracellualr. In addition the polarity restricts certain substance movement across the walls.
Serve as the selective channels  for the  influx of certain substances into the cells, and the out flux of wastes.This is through ion channels for the movements of ions across.
Provide insulation to the cells,to maintain the constant internal temperature,this is through the presence of lipids as( Phospholipids and cholesterol).The latter prevent the clogging of the lipids in the cell membrane therefore preventing frozen up of the cell membrane,providing insulation.
Separation of metabolic process in the cell.
Explanation:
Cell membrane-This is present in all cells.But the variation of its constituents makes it unique to each cell. Although it performs the same role, the location and role the cells it bounded, reflects its  constituents, it is made up of lipids, carbohydrate, protein and cholesterol
 
        
             
        
        
        
The uterine lining of the female's uterine cycle is shed during the menstrual phase. Menstrual cycle is a reoccurring cycle which begins at menarche and ends at menopause. During menstrual cycle, the endometrial lining prepares for pregnancy.
        
             
        
        
        
Its "C" because the earth only has a certain amount of oil but yet we have endless amount of sun, solar, and wind 
        
                    
             
        
        
        
Answer:stream Flow or the channel runoff
Explanation:
Explanation:
 
        
             
        
        
        
<span>Since the child has never been away from his parents and siblings and also he is only 4 years old it is better to have one of them stay with the child. The presence of a family member will reinforce trust and provide support to the kid.</span>