I think the best answer would be A. since the number of prairie dogs decreased from the picture on the left to the picture on the right. Hope this helped :p
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.
1) carries food and oxygen to the different cells of the body; 2) carries body wastes away; 3) protects the body from diseases; and 4) serves as the body's defense system.
it is one of the transport systems of the human body that is composed of the heart, the blood and the blood vessels. Its functions include: 1) carries food and oxygen to the different cells of the body; 2) carries body wastes away; 3) protects the body from diseases; and 4) serves as the body's defense system.