Essential Knowledge 3.C.2

Biological systems have multiple processes that increase genetic variation.

The imperfect nature of DNA replication and repair increases variation.

The horizontal acquisitions of genetic information primarily in prokaryotes via transformation (uptake of naked DNA), transduction (viral transmission of genetic information), conjugation (cell-to-cell transfer) and transposition (movement of DNA segments within and between DNA molecules) increase variation.

Sexual reproduction in eukaryotes involving gamete formation, including crossing-over during meiosis and the random assortment of chromosomes during meiosis, and fertilization serve to increase variation. Reproduction processes that increase genetic variation are evolutionarily conserved and are shared by various organisms. NOTE: The details of sexual reproduction cycles in various plants and animals are beyond the scope of the course and the AP Exam. However, the similarities of the processes that provide for genetic variation are relevant and should be the focus of instruction.

Students should be able to:

LO 3.27 Compare and contrast processes by which genetic variation is produced and maintained in organisms from multiple domains.

LO 3.28 Construct an explanation of the multiple processes that increase variation within a population.