BIOL 1240 Midterm Ultimate Study Guide

Ploidy

The number of sets of chromosomes in a cell, with haploid ($n$) having one set and diploid ($2n$) having two sets.

Haploid

A cell or organism that contains one complete set of chromosomes, denoted as $n$.

Diploid

A cell or organism that contains two complete sets of chromosomes, denoted as $2n$.

Binary Fission

A method of asexual reproduction where a single organism divides into two identical daughter cells, preserving ploidy.

Mitosis

A type of cell division that results in two genetically identical diploid daughter cells from a single diploid parent cell.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in four genetically distinct haploid gametes.

Crossing Over

The process during meiosis where homologous chromosomes exchange genetic material, increasing genetic diversity.

Sister Chromatids

Identical copies of a chromosome that are connected by a centromere, formed during DNA replication.

Non-Sister Chromatids

Chromatids from homologous chromosomes that are not identical; they represent different allele forms.

Homologous Chromosomes

A pair of chromosomes, one from each parent, that are similar in shape, size, and gene content.

Telophase

The final stage of mitosis and meiosis where the chromosomes decondense and nuclear envelopes reform around the separated daughter nuclei.

Cytokinesis

The process that follows mitosis or meiosis where the cytoplasm divides, forming two distinct daughter cells.

Vegetative Reproduction

A form of asexual reproduction in plants where new individuals arise without the production of seeds or spores.

Parthenogenesis

A form of asexual reproduction where an egg develops into a new organism without fertilization.

Clones

Offspring that are genetically identical to their parent organism, produced through asexual reproduction.

Alleles

Different forms of a gene that can exist at a specific locus on a chromosome.

Prophase

The first stage of mitosis and meiosis where chromosomes condense and become visible.

Metaphase

The stage of mitosis and meiosis where chromosomes align along the equatorial plane of the cell.

Anaphase

The phase of mitosis and meiosis in which sister chromatids or homologous chromosomes are pulled apart to opposite poles.

Telophase I

The stage in meiosis where two daughter cells are formed, each containing half the number of chromosomes.

Meiotic Progression

The stages in meiosis that lead to the formation of haploid gametes with genetic variation.

Life Cycles of Eukaryotes

The series of stages through which a eukaryotic organism passes in its development, including haplontic, diplontic, and alternation of generations.

Recombination

The process by which genetic material is mixed and exchanged between homologous chromosomes during meiosis.