Chap. 15 (Vocab) Flashcards
Chromosome Theory of Inheritance
Genes are located on chromosomes and behavior of chromosomes during meiosis explains the patterns of inheritance
Sex-linked Gene
Genes located in either sex chromosome
X-linked Genes
Genes on X chromosome
Y-linked Genes
Genes on Y chromosome
- Only a few
Duchenne Muscular Dystrophy
Weakening of muscle + loss of coordination
Hemophilia
Absence of proteins required for blood clotting
- When person is injured, bleeding is prolonged
Barr Body
Condensed + inactive X chromosome found in the cells of female mammals
- In innerside of nuclear envelope
Mosaic
Some cells have a normal genetic code while others carry a mutation, often resulting from an error in early cell division
Linked Genes
Genes located on same chromosome + are usually inherited together
Genetic Recombination
Genetic material is exchanged between organisms, resulting in offspring with new combinations of traits that differ from both parents
Parental Types
Offspring that inherit a combination of traits that exactly match one of the two parents
Recombinant Types
Offspring or individuals that possess a combination of alleles (genetic traits) that are different from either parent
- Result of genetic recombination
Genetic Map
Genetic loci along a chromosome
Linkage Map
Chromosomal map based on recombination frequencies
Map Units
Distance between genes based on recombination frequency
- 1 unit = 1% recombination frequency
Nondisjunction
Failure of the chromosomes to separate, which produces daughter cells with abnormal numbers of chromosomes (more than normal)
Aneuploidy
Abnormality in the number of chromosomes in a cell due to loss or duplication
- more or less
Monosomic
Only has one copy of a particular chromosome, instead of the usual two copies found in a pair
- X and I
Trisomic
Presence of an extra chromosome — or three instead of the usual pair
- X X and I
Polyploidy
Organism has more than two complete sets of chromosomes in its cells
Duplication
Segment of DNA is copied, resulting in multiple identical copies of a gene within an organism’s genome
Inversion
Segment of a chromosome breaks off and reattaches in the reversed direction
Translocation
Piece of a chromosome breaks off and attaches to a different chromosome
Genomic Imprinting
Copy of a gene is expressed while other is supressed
