Answer:
The chance of a normal couple having a child with down syndrome is 1 to 600 births.
Explanation:
Down syndrome is a genetic flaw that occurs when the fetus is being formed.
A human cell considered normal has 46 chromosomes, divided into 23 pairs. For some unknown reason, an error may occur at the beginning of embryonic development and an extra chromosome is created, which binds to par 21. The result is cells with 47 chromosomes. This causes the said syndrome.
It is important to know that this failure happens at random. It is nobody's responsibility. It has not been proven to date that lifestyle, actions during pregnancy, smoking, drinking, medicines, environmental factors or kinship between the couple can influence this occurrence. She is not contagious either. The likelihood of a normal couple having a child with the syndrome is approximately 1 to 600 births.
Answer: Proteins are made using DNA as a template. The DNA is turned into RNA, and the RNA is then turned into DNA.
A change in these nucleotides could end up making some part of the protein different. A single nucleotide change could be silent (no change in the protein) or could change a single amino acid (amino acids are the building blocks of proteins). If that was an important amino acid, the protein might not function at all! A silent change can occur because the same set of nucleotides sometimes makes the same final amino acid (for example, reading "gcc" "gca" "gcg" or "gct" nucleotides all mean "alanine" amino acid).
The deletion of a single nucleotide, or the addition of one, can change the entire sequence of amino acids that come after it! Nucleotides are read in sets of three, so this throws off how the DNA is read. If would be like turning "The brown fox jumps over the dog" into "The gbrow nfo xjump sove rth edo g". Completely different! All of the words are thrown off.
I know it is long but I hope it helped
:D
<span>In real life, the presence of friction. Choice B</span>
