Answer:
8,324,608 different possible combinations of chromosomes.
Explanation:
Answer: the development of the enzyme Rubisco and evolution of oxygenic photosynthesis.
Explanation: One can pick many key steps in early evolution: the development of the first cells, oxygenic photosynthesis, endosymbiosis leading to eukaryote organisms.
One important step was the mutation to the enzyme ribulose bisphospate carboxylase oxygenase (Rubisco) which enabled oxygenic photosynthesis.
The cyanobacteria that had Rubisco changed the planet’s atmosphere by producing oxygen as a by-product of photosynthesis. They were the most successful organisms of the time and have continued as a successful and ubiquitous group of organisms for billions of years.
The production of oxygen changed the direction of evolution profoundly. Later endosymbiosis led to the evolution of plants, with cyanobacteria the ancestors of chloroplasts, making Rubisco one of the most common enzymes on the planet.
The DNA has to replicate during the S phase so that each new cell that is forming can get it's own replica of the original cell's DNA molecule
Sharks, whales, and dolphins share similar features such as body shape and the position of fins. However, sharks have gills for breathing, while whales and dolphins have lungs. Sharks and dolphins are similar in construction because they need their parts to complete many of same functions.
For example:
The dorsal fins that are found in both shark and dolphin are due to convergent evolution and they are actually not from common ancestor.
Chemical energy , as starch .