AP Biology/Heredity
Introduces how traits are passed down from one generation to the next.[1]
Objectives and Skills
[edit | edit source]Topics may include:[2]
- The process and function of meiosis
- The concepts genetic diversity
- Mendel’s laws and probability
- Non-mendelian Inheritance
- Factors affecting inheritance and gene expression
Pedigree
[edit | edit source]- Dominant - One of the parents must have the trait; every affected child of non-affected parents has one affected parent.
- Recessive - Neither parents are required to have it as they're heterozygous; the male parent is affected, but there is an offspring with parents that are not affected; if any affected individual has 2 parents to which they're not affected, then it's recessive.
- Autosomal - Both males and females are equally liked; parents aren't affected. Son or daughter is affected; affected son with an affected parent.
- Sex-linked - Males are more affected.
- X-linked - Carrier's female.
- Polygenic traits - Traits controlled by multiple genes instead of just one gene.
- Recombinant phenotypes - Combinations of traits that are different from either parent. Crossing over causes this.
- Non-disjunction - Failure of the chromatids of the homologous chromosomes/sister chromatids to separate.
- Polyploidy - A condition in which the cells of an organism have more than two paired (homologous) sets of chromosomes.
- Trisomic - Down Syndrome
- Monosomic - Turner's Syndrome
- Alteration of chromosome structure
- Deletion - Removes a chromosomal segment.
- Duplication - Repeats a segment.
- Inversion - Reverses a segment within a chromosome.
- Translocation - Moves a segment from 1 chromosome to another, non-homologous one.
- Inheritance from Dad
Deletion of a particular segment of chromosome 15 causes...
- Prader-Willi Syndrome - Intellectual disability, catatonia, excessive weight gain, and small hands and feet.
- Angelman syndrome - Uncontrollable laughter and jerk movements.