6.G Meiosis & sexual reproduction

Sexual reproduction

A form of reproduction that requires each organism to provide ½ of the DNA to create an offspring which increase genetic variation since each offspring is unique.

Diploid

A non-sex cell containing the exact same DNA as the parent cell. (contains 2 sets of DNA, 1 from mom and 1 from dad, 2n)

Haploid

A sex cell containing only half the DNA from the parent cell. (Gametes contain only 1 set of DNA, 1n)

Meiosis

A type of cellular division that results in 4 genetically unique haploid sex cells (sperm/egg) needed for sexual organism reproduction.

Somatic cell/ Autosome

Any non-sex cell in the body. (ex. skin, nerve, bone, blood)

Mitosis

Cell division that results in production of 2 exact copies of the parent cell. Consists of 4 phases: prophase, metaphase, anaphase, telophase> followed by cytokinesis

Law of Independent Assortment

Chromosomes are randomly divided into sex cells resulting in 4 unique gametes. This process helps to ensure genetic variation since each of the cells are different.

Homologous Chromosomes

Chromosomes that code for the same genes (1 from mom, 1 from dad). Humans have 23 pairs of homologous chromosomes (equals a total of 46 chromosomes)

Crossing Over

Exchange of DNA between homologous chromosomes. Increases genetic variation since it results in each chromosome being unique/different from another.

Asexual Reproduction

Offspring/daughter cells arise from a single organism/cell. Offspring will have the exact same DNA as the parent cell and will look exactly like the parent.

Gametes

Sex cells (egg and sperm) produced from a somatic germ cells

Genetic Variation

Variations of the same gene that create diversity in a species. (Ex. height, color, strength...)

Binary fission

orm of asexual reproduction that prokaryotic cells use to replicate