Allison was born with an extra 21st chromosome, which makes her more susceptible to heart defects and mental retardation. Allison has ____.
A) fetal alcohol syndrome
B) Tay Sachs disease
C) sickle cell anemia
D) Down syndrome

Question

Quizplus · Accepted Answer

Down syndrome is caused by an extra copy of chromosome 21, which is also known as trisomy 21. This condition increases the risk for heart defects, intellectual disability, and other health problems. Fetal alcohol syndrome is caused by alcohol exposure during pregnancy and can cause developmental delays, facial abnormalities, and other health problems. Tay Sachs disease is a genetic disorder that affects the nervous system and can cause progressive deterioration of mental and physical abilities. Sickle cell anemia is a genetic blood disorder that affects the shape and function of red blood cells.

Allison Was Born with an Extra 21st Chromosome, Which Makes