Pulmonary valve - connects right ventricle and pulmonary trunk (which divides into right and left pulmonary arteries). It is a semilunar valve
In lakes and ponds there is a whole ecosystem, with its animals and plants. Between them they are in charge of maintaining the entire habitat in favorable conditions for living. The fish tank does not have that cleaning system.
its due to diffusion this happens some times osmosis as well
All elements are made of atoms
