D. Heterotrophs
EXPLANATION: Heterotrophs cannot produce its own food so it kills and eats other organisms for energy. Plants are autotrophs which means they can make their own foods.
D. Parasitic will be you answer.
Short answer - to breathe.
Long answer - the black streaks on the trunk of birch trees are called lenticels, and their function is to enable the exchange of gases between the tree and the air. So, in a way, this makes the whole process of photosynthesis a lot easier for birch trees.
Answer: b. Nitrogen; Oxygen
Explanation:
The air is a mixture of gases in the following percentage;
Nitrogen; 78%
Oxygen : 21%
Carbon(IV)Oxide : 0.03%
Argon : 0.9%
Others ( minute traces of Neon, Helium, Methane e.t.c) : 0.17%
