A. Sound is a form of mechanical energy
<h2>Down Syndrome</h2>
Explanation:
Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21
- Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21
- Down syndrome is usually caused by an error in cell division called nondisjunction which results in an embryo with three copies of chromosome 21 instead of the usual two
- Prior to or at conception, a pair of 21st chromosomes in either the sperm or the egg fails to separates
- With development in embryo the extra chromosome is replicated in every cell of the body;this type of Down syndrome which accounts for 95% of cases is called trisomy 21
- Maternal age is the only factor that has been linked to an increased chance of having a baby with Down syndrome resulting from nondisjunction;here environmental agents such as drugs, chemicals, and radiation act as mutagens which induce mutation in the fetus
Answer:
Crop rotation is the method of growing a series of different types of crops in the same area across a sequence of growing seasons (China does this). It reduces dependence on just one type of nutrients, it also helps control pests and weeds by the plants developing a resistance all at once.
