Answer:
During meiosis, an event known as chromosomal crossing over sometimes occurs as a part of recombination. In this process, a region of one chromosome is exchanged for a region of another chromosome, thereby producing unique chromosomal combinations that further divide into haploid daughter cells.
Answer:
faced a struggle for survival
Explanation:
The woolly mammoths became extinct, unlike the other species, because the woolly mammoths faced a struggle for survival due to changing of environmental conditions. Global warming is the main cause of extinction of woolly mammoth which destroy their habitats about 10,500 years ago. The environmental conditions are not favourable for them so they faced struggle for survival which causes extinction of woolly mammoth.
The answer is B , i hope this helps
Answer:
I am guessing The second Cause only petroleum stay in the top of water
