The surface of a leaf has many tiny pores, called stomata. The stomata allow carbon dioxide into the leaf so that photosynthesis can occur. They also allow water to leave the leaf by transpiration. Plants that grow in full sunlight usually have most of their stomata on the shaded undersides of their leaves.
Genetic
since we are made from our dna
Every organism is unique, even though the nucleotides making up DNA are all the same, because the structure is different in every organism. In other words, it's just the order in which nucleotides are placed that differs each organism from one another.
The double-helix shape of DNA.