Explanation:
In the majority of cases, the extra copy of chromosome 21 comes from the mother in the egg.
In a small percentage (less than 5%) of cases, the extra copy of chromosome 21 comes from the father through the sperm.
In the remaining cases, the error occurs after fertilization, as the embryo grows.
Answer:
its faster because our economy is better that others
Explanation:
Answer:
1. Nucleoid
2. Plasmid
Explanation:
Prokaryotes are groups of organisms characterized by the lack of a membrane-bound nucleus in their cell. Due to this, the genetic material (DNA) of prokaryotes are found naked i.e. not housed. The DNA of a prokaryote is arranged in a single coiled chromosome located in a region of the cell called NUCLEOID.
However, some prokaryotes e.g. bacteria carry genes on extrachromosomal pieces of circular DNA called PLASMID. Plasmids carry certain genes like antibiotic resistance genes.
The parts wich are derived from these three areas include:the cerebellum,the brain stem of the brain stem consists of the parts:the midbrain,bridge brain,the medulla oblongata.other parts of the brain including the thalamus,hypothalamus and limbic device.
The answer is A .
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