Nucleotides are a base pair and they fit together because their shape allows them to bond. The A-T pair frames two hydrogen bonds. G-C forms 3. As the strands bond they hold the Base Pairs of DNA together
Answer:
8.7 million
Explanation:
About 8.7 million (give or take 1.3 million) is the new, estimated total number of species on Earth -- the most precise calculation ever offered -- with 6.5 million species on land and 2.2 million in oceans.
The Answer -
A. The amount of land available for lumber production decreases.
Do to the Urban development there is fewer land and less trees to grow and cut down for lumber, which can lead in a decrees if production for lumber.
This means that a single carbon atom can form up to tetravalent bonds with other atoms