Trees are very important natural resources. They are the source of food, shelter and habitat. We get various woods, timber , fodder from the forest. Trees hold the soil firmly. Forests helps in conducting water cycle. If trees are cut down then environmental pollution will increase because trees purify the Air. Land pollution , air pollution , water pollution may increase. Biodiversity can be affected.
Adenine which is a purine base, always pairs with the pyrimidine Thymine in DNA and Uracil(also a pyrimidine) in RNA. The bond which is present between the two bases is a double hydrogen bond.
Guanine which is also a purine base, always pairs with the pyrimidine Cytosine, in the case of both, DNA and RNA. The bond which is present between the two bases is a triple hydrogen bond and hence, is stronger than the A-G double bond.
D. Cones
Cycads are basically composed of woody plants which have roots, a stem, leaves and reproductive structures called Cones. These cones differ from each other depending on the plant whether it is female or male. These cones vary from shape, size, color, etc. based on the sex of the plant.
