Answer :There was enough oxygen in the atmosphere to support a major burst of life on Earth
Explanation:
The Great Oxygen Event marks the time, approximately 2.5 billion years ago, when there was enough oxygen in the atmosphere to support a major burst of life on Earth
For the first half of the Earht's history, there was no oxygen in the atmosphere. It was inhabited only by single-celled organisms.Of those simple life forms, the cyanobacteria may have. evolved a way to take energy from sunlight, and used it to make sugars out of water and carbon dioxide. They used the same chemical process we know as photosynthesis. This released vast quantities of oxygen into the atmosphere and triggered the evolution of complex life.
Answer:
Sharks, in their basal form have been on Earth for hundreds of millions of years. They were the first to develop a stream-like, torpedo shaped body and created a niche for themselves. Their aerodynamic body shape has evolved to allow for efficient and dynamic movement in water. Having a cartilage instead of bones allowed them to grow large and still be relatively light and buoyant . After they've evolved flexible, protruding jaws, there wasn't much to change. They were able to adapt and exploit all the water habitats as the world was changing.
Explanation:
Cephalization describes the process by which organisms develop a distinct head. The head of a cephalized organism contains a concentrated group of nerves, or brain, that controls the rest of the organism, as well as specialized organs for consumption and perception, like mouths, eyes and ears. Cephalized organisms exhibit a distinct division between parts of the body; they have a front, back, top and bottom. These animals comprise the bulk of animals that are encountered on a daily basis.
sea star following organisms exhibits cephalization
Ricin comes under the category of functionally related toxins, in a combination known as RIPs (ribosome inactivating proteins). This disables ribosomes and stops the process of protein synthesis.
They directly associate with and inactivate the ribosomes or modify the factors taking part in the process of translation, generally the elongation step. These proteins bring about depurination of adenine at position 4324 in the 28 S rRNA.
This further inhibits the generation of a critical-stem-loop configuration to which the elongation factor is considered to combine at the time of the translocation step of translation. The ultimate outcome of this activity is the complete inhibition of cellular translation.
the answer is Insertion mutation :)
(search up "types of mutations")