Answer:
Population trend refers to changes over time and can include changes in ranging behavior (e.g., distance and route) and distribution, biogeography (e.g., size of population) and life-history (e.g., birth and death rates).
 
        
             
        
        
        
Gametes are the only haploid cells  
        
                    
             
        
        
        
The first species to colonize a barren area is a Pioneer Species
        
             
        
        
        
The action in which particles go from a high area of concentration to a lower concentration is called diffusion!
        
             
        
        
        
Answer:
The number of habitats falls below a critical level.
Explanation:
The possible reason for extinction is that the number of habitats falls below a critical level. This makes it impossible for organisms to survive. 
- A habitat is the dwelling place of living organism in an ecosystem. 
- The resources and other materials that ensures the survival of an organism are made available in the habitat. 
- When a habitat begins to thin out and can no longer support organisms, then extinction will ensue.