Need help badly thanks.
Down Syndrome is
A.a sex-linked trait
B.a recessive trait
C.the result of having two few chromosomes
D.the result of having an extra chromosome
I'm here to help! To determine the correct answer, let's break down the options and try to understand each one.
A. Down Syndrome as a sex-linked trait: Sex-linked traits are genetic traits that are carried on the sex chromosomes (X and Y). Down Syndrome, however, is not caused by a gene on the sex chromosomes. So, we can eliminate this option.
B. Down Syndrome as a recessive trait: Recessive traits are only expressed when an individual has two copies of the recessive allele. Down Syndrome is not a recessive trait since it is not caused by inheriting two copies of the same gene. Therefore, we can eliminate this option as well.
C. Down Syndrome as the result of having too few chromosomes: This option is not correct. Down Syndrome is actually caused by having an extra copy of chromosome 21, rather than having too few chromosomes.
D. Down Syndrome as the result of having an extra chromosome: This is the correct answer. Down Syndrome, also known as trisomy 21, is caused by the presence of an extra copy of chromosome 21.
To summarize, the correct answer is D. Down Syndrome is the result of having an extra chromosome.