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
Answer:
The effects of weathering disintegrate and alter mineral and rocks near or at the earth's surface. This shapes the earth's surface through such processes as wind and rain erosion or cracks caused by freezing and thawing. Each process has a distinct effect on rocks and minerals.
When we use water, we often use too much. We waste it. When washing cars, showering, brushing our teeth etc. Because of wastefulness, there are places that don't have the luxury of being able to wash their car well, and can't water their lawns for more than a few minutes a day.
I hope I was able to help. Best of luck.
Color blindness is a recessive x-linked trait in humans. In a family where the mother is color-blind, and the father is normal, the probability of their having a color-blind son is 100%.
Color blindness is a recessive x chromosome liked recessive disease which is more prone in males than in females. As the mother is color-blind she has both the alleles of colorblindness while the father is normal with both x chromosome and y chromosome normal.
So if the parents have a boy, he will always receive an x chromosome with colorblindness gene from the mother and a normal y chromosome from the father always. Thus, the probability of having a colorblind boy will be 100%.
To know more about colorblindness refer to the link below
brainly.com/question/2094919
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