Mendelian Genetics

• Homozygous: Having two identical alleles of a particular gene.
• Heterozygous: having two different alleles of a particular gene or genes
• Allele: A variant form of a gene; one member of a pair of alternative forms of a gene at a specific locus on a chromosome.
• Genotype: The genetic makeup of an individual that determines their phenotype.
• Phenotype: the observable characteristics of an organism, including physical traits such as eye color, hair color, height, etc.
• Law of Segregation: The law states that the genes for a particular characteristic are found on different chromosomes and that the allocation of the gene copies is completely random.
• Law of Independent Assortment: This principle states that when gametes (sex cells) are formed from parental cells, the inheritance of one trait does not affect the inheritance of another unrelated trait.
• Punnett Square - A diagram used to predict the possible offspring of a cross between two organisms.

  
• What is nondisjunction?

  Nondisjunction is a genetic phenomenon where chromosomes fail to separate properly during cell division, resulting in an abnormal distribution of chromosomes in the daughter cells. This can lead to genetic disorders such as Down syndrome.
• Aneuploidy: the condition of having an abnormal number of chromosomes in a haploid set
• Duplication: a part of a chromosome is copied.
• Deletion: a part of a chromosome is removed.
• Inversion: chromosomal region is inverted/reversed so that it points in the opposite direction.
• Translocation: a piece of a chromosome gets attached to another chromosome.
• There are 2 types of translocation:

  1. Reciprocal translocation: the exchange of segments between 2 chromosomes.
  2. Non-reciprocal translocation: a chunk of a chromosome moves to another.