Answer:
hope this helps
Explanation:
About 95 percent of the time, Down syndrome is caused by trisomy 21 — the person has three copies of chromosome 21, instead of the usual two copies, in all cells. This is caused by abnormal cell division during the development of the sperm cell or the egg cell.
Out of the following given choices;
<span>A. </span>cause their nest-guarding activity to drop
<span>B. </span>change male characteristics to female characteristics
<span>C. </span>disrupt the estrogen receptors
<span>D. </span>cause the males to become even more aggressive
The answer is A. The males would begin to search for the females for mating and hence reduce their guard of the nests. This would result in easy access of the nests to enemies and predators of fish eggs and fingerlings.
Answer:
Continuous variations are formed due to chance segregation of genes during gamete formation, crossing over and chance combination during fertilization. They can increase adaptability of the race but cannot form new species.
Overconsumption – situation where resource use has outpaced the sustainable capacity of the ecosystem. ...
Overpopulation – too many people for the planet to sustain. ...
Acid rain.
Biodiversity loss.
Deforestation.
Desertification.
Global warming/climate change.
Habitat destruction.
source - wikipedia.org
