Chromosome Number and Structure Review

Practice flashcards summarizing key concepts related to chromosome number and structure, including karyotypes, chromosome behavior, aneuploidy, polyploidy, and structural mutations.

What are the key characteristics of chromosomes in terms of number, shape, and genome content across species?

Related species tend to have similar numbers of chromosomes; it is species-specific.

What is a karyotype, and what can it be used to detect?

Organized visual display of chromosomes that can identify abnormalities in chromosome number or structure.

What distinguishes euploid cells from aneuploid cells?

Euploid cells have a complete set of chromosomes (n, 2n, 3n); aneuploid cells have a number of chromosomes that is not euploid.

What happens during nondisjunction in meiosis I versus meiosis II?

In meiosis I, homologs fail to separate; in meiosis II, sister chromatids fail to separate.

Which autosomal trisomies are compatible with live birth?

Trisomies of chromosomes 13 (Patau syndrome), 18 (Edwards syndrome), and 21 (Down syndrome).

What is gene dosage and why is it important in animals?

Gene dosage refers to the number of copies of a specific gene; it is crucial for normal functioning as animals are highly sensitive to imbalances.

How does polyploidy affect traits like fruit and flower size?

Polyploidy increases fruit and flower size.

What is hybrid vigor?

Hybrid vigor refers to the improved growth, fruit and flower production, and disease resistance in progeny resulting from crossing inbred lines.

What is the cause of cri-du-chat syndrome?

Cri-du-chat syndrome is caused by a deletion of part of chromosome 5 and is characterized by a distinctive cat-like cry in infants.

What are the two types of chromosome inversions?

Paracentric inversion (centromere outside of the inverted region) and pericentric inversion (centromere within the inverted region).