Answer:
Natural selection leads to evolution.
The major causes of the greenhouse effect is excessive carbon dioxide gas in the atmosphere. The greenhouse effect is a process that warms the Earth's surface. When the Sun's energy reaches the Earth's atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by green house gases, such as carbon dioxide, water vapor, metahne, nitrous oxide, and ozone. The absorbed energy warms the atmosphere and the surface of the Earth.
Yes, enzymes can be found in every type of living beings
The nucleotides are bonded together via hydrogen bonds making it easy for the dna to be split in half and replicated