Crossing over happens in Meiosis 1 only. In Prophase 1 a cells chromatin (chromatin = chromosomes that have not condensed yet) condense and pair up forming homologous chromosomes (paired = XX (2 chromosomes together)). When this happens segments/ alleles of the chromosomes pairing up swap over. This creates genetic diversity as each chromosome is different, it has parts from its pair. This leaves every chromosome unique and individual.
I hope this helps, sorry some of the vocab is rather technical. By the way I would suggest watching the
'Crash Course: Meiosis' on YouTube, this really helped me when I was learning this topic. :D
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mountains and rivers because a geographical barrier can be a mountains range, a large canyon, a body of water
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vitamin A is essential because consuming too much supplemental vitamin A during pregnancy can cause birth defects.
Hope this helps!
Bacteria recycle matter in an ecosystem through breaking down of the organic debris.
<h3>What is decomposition?</h3>
Decomposition is defined as the break down of dead organic matter in nature by microorganisms such as bacterias thereby releasing elements such as nitrogen that can be reused again.
Bacterias, protozoa and some fungi are known as decomposers in the food chain of an ecosystem which recycles elements found in dead organic matter by breaking them down.
Learn more about ecosystem here:
brainly.com/question/26551655
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A cinder cone<span> or </span>scoria cone<span> is a steep </span>conical hill<span> of loose </span>pyroclastic<span> fragments, such as either volcanic clinkers, cinders, volcanic ash, or </span>scoria<span> that has been built around a </span>volcanic vent.[1][2]<span> They consist of loose pyroclastic debris formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that often is beautifully symmetrical; with slopes between 30-40°; and a nearly circular ground plan. Most cinder cones have a bowl-shaped </span>crater<span> at the summit.</span><span>[1]
hope this helps hope i am brainliest i need one more </span>
