Two alleles for each trait segregate during gamete formation,
 then unite at random, one from each parent during fertilization

Mendel's 2nd law: (Principle of independent assortment)

- genes for different traits assort independent of one another

• True nuclues
• multicellular species such as plants, animals, and other fungi

• the same chromosomes inherited from different parents

• Bacteria and archaea
• Their chromosomes are not contain within a membrane -bound nucleus of the cell.
• located in cytoplasm called the nucleoid

• Cell division in bacteria - binary fission

• Asexual Reproduction

• cells produced are genetically identical to each other and the parent
    cell they were derived from

• Chromosomes are replicated during S-phase, forming “sister chromatids

Phases of Mitosis

               Prophase

• chromosomes line up at middle (metaphase plate) of cell

          Anaphase

• sister chromatids are separated and migrate to opposite poles

- sister chromatids are finished migrating; new nuclear envelope
  begins to form, cytokinesis begins

Meiosis

- “Sexual Reproduction”

- cells produced are genetically different from each other and the
  parent cell they were derived from

- occurs in “germ cells” and produces “gametes”

- involves two cell divisions and produces 4 cells

wild-type alleles

• most common allele found in wild
• not necessarily dominant or recessive

mutant alleles

• any allele that is not wild-type
• not necessarily dominant or recessive

Incomplete dominance

• phenotype of heterozygotes appears to be the

  intermediate of two traits together

Codominance

•  both phenotypes are expressed in the heterozygous

  individuals

• example: ABO blood groups

Epistasis

• one gene interferes with the phenotypic expression of another

Polygenic inheritance

• multiple genes combine to generate one phenotype
• often effect of multiple genes is additive

Pleitropy

-one gene that is responsible for many phenotypes

Sex-influenced traits

- the phenotype observed for a given genotype is somehow
  influenced by the sex of the individual