-Water evaporates and condenses into clouds, then the clouds are blown over the ocean, and it rains.
-Water from a mountain flows down and into a river. The river empties into an ocean.
The element carbon makes long chains forming, single, double or triple bonds with itself.
Answer:
If I am correct it is when the weaker individuals or mutated individuals are killed of by other predators or by nature. Because they cannot survive this is natural selection because they are killed of by nature. Then if they are weak their species will go extinct, thus they are naturally selected to die and only the strong species remain.
First pic :
plants do not have cell membranes
(plants have BOTH cell membranes and cell walls)
second pic:
ATGC
(opposite strand of the DNA TACG)
third pic:
the second choice
(selectively permeable means only specific molecules could get in and go out)
fourth pic:
option 2
(cellular respiration takes sugar (or food) and makes it into ATP energy. this is what makes us have energy after we eat)
I really hope this helped :))