Mars and Earth are very different planets when it comes to temperature, size, and atmosphere, but geologic processes on the two planets are surprisingly similar. On Mars, we see volcanoes, canyons, and impact basins much like the ones we see on Earth
But roughly 2.45 billion years ago, the isotopic ratio of sulfur transformed, indicating that for the first time oxygen was becoming a significant component of Earth's atmosphere, according to a <span>2000 paper in Science</span>. At roughly the same time (and for eons thereafter), oxidized iron began to appear in ancient soils and bands of iron were deposited on the seafloor, a product of reactions with oxygen in the seawater."What it looks like is that oxygen was first produced somewhere around 2.7 billion to 2.8 billon years ago."It looks as if there's a significant time interval between the appearance of oxygen-producing organisms and the actual oxygenation of the atmosphere."
Answer: yoga, peace, relaxing, water, ice, thinking, not stressing
Answer:
They have uncoiled to form long, thin strands.
Explanation:
Chromosomes are present in cell nucleus and consist of chromatin. Genes are present in linear order on chromosomes. The chromosomes become visible under the microscope as distinct structures during cell division. When cells are not dividing, the chromosomes decondense to loose their individuality and make the mass of chromatin.
Chromatin is complex of DNA and packing proteins. As the cells enter the prophase stage of cell division, condensation of chromatin occurs and individual chromosomes become visible under microscope. Before that (during interphase), chromosomes are not visible as they are present in decondensed form.
