Question

A karyotype reveals that a developing rat fetus, which died before birth, carried an extra copy of chromosome 1. Genetically, this individual would best be described as showing __________.

Answer 1

A developing rat fetus with an extra copy of chromosome 1 would be classified as having trisomy, wherein there are three copies of a particular chromosome instead of the normal two. This is a type of aneuploidy and can lead to genetic imbalances and developmental issues, similar to human disorders such as Down Syndrome.

Step-by-step explanation:

Genetically, a developing rat fetus with an extra copy of chromosome 1 would best be described as showing trisomy. This condition is a type of aneuploidy, where the individual does not have the typical number of chromosomes for its species. In humans, similar conditions are exemplified by genetic disorders such as Down Syndrome, where there is an extra copy of chromosome 21, leading to physical and developmental changes.

A karyotype can reveal these chromosomal abnormalities, which can also include large deletions, insertions, or translocations of DNA segments, potentially leading to genetic imbalances and developmental issues.