Lecture on Genomes, Chromosomes, and Genetic Conditions

These flashcards cover key terms and concepts related to genomes, chromosomes, chromosomal abnormalities, and genetic conditions.

Genome

All the genes an organism can possess.

Chromosome

A collection of genes organized onto a single piece of DNA.

Prokaryotic DNA Packaging

Prokaryotic DNA is packaged as a circular chromosome.

Eukaryotic Genomes

Almost all eukaryotes have genomes split onto more than one chromosome.

Relationship between Chromosome Number and Genome Size

There is virtually no relationship between chromosome number and genome size.

States of DNA Packaging

Metaphase chromosomes and interphase chromosomes are the two states of DNA packaging.

Centromere

A constricted region where spindle fibers attach during mitosis.

Cohesion

A protein that holds the sister chromatids together.

Telomeres

Protective caps that prevent unraveling and preserve the integrity of linear chromosomes.

Aneuploidy

Presence of extra or missing chromosomes.

Trisomy 21

Down’s syndrome, which is the presence of an extra 21st chromosome.

Klinefelter’s Syndrome

A condition in men who have an extra X chromosome (XXY).

Turner’s Syndrome

The only tolerated missing sex chromosome, characterized by having one X chromosome.

Cri-du-chat Syndrome

A genetic disorder caused by a deletion on the p arm of chromosome 5, leading to abnormal larynx development.

Intra-chromosomal Rearrangement

A structural change where a segment of a chromosome breaks and rearranges within the same chromosome.

Polyploidy

Condition where an organism has more than two sets of chromosomes.

Autopolyploid

Doubling of the existing diploid genome.

Allopolyploid

Chromosome sets come from different but closely related species.

Copy Number Variants

A type of genetic alteration where sections of the genome are deleted or duplicated.

Reciprocal Translocation

Rearrangement that results from a single break in each of two chromosomes.

Robertsonian Translocation

Whole arm exchanges between acrocentric chromosomes.

Effects of Chromosomal Inversion

Inversion involves rearranged regions on a chromosome, affecting meiosis outcomes.