When a person is born they get one chromosome from the mom and one from the dad. A female has XX chromosomes a male has XY Cromosomes. So a male would get the Y from the dad and the X from the mom.
        
                    
             
        
        
        
Yes people are trying to plant more trees and promote awareness on afforestation and some have even started making rules the 'clean air act'
        
             
        
        
        
The organelle that maintains pressure against the cell wall, so that the plant cell keeps it shape, is
the (a) central vacuole.
        
             
        
        
        
Answer:
Free fall.
Explanation:
When astronauts sleep in space, they sleep in small cabins or in sleeping bags that are attached to the wall or ceiling of the station. Everything is weightless as there’s no gravity in space. So while sleeping there is a chance of floating around and bumping into things. Astronauts use sleeping bags that can be tethered to the wall or ceiling to solve this problem. Also the tethered sleeping bags provide a normal sleeping environment to the astronauts  as they can feel pressure on their back and head.  Their sleeping cabin is well ventilated as they can wake up with breathing trouble as a result of the inhalation of their own exhaled carbon dioxide which formed around their heads as a bubble. They use earplugs and a sleep mask to block the noise and light and can sleep vertically or horizontally. Compared to earth, sleeping is a bit different in space.