BIO152

Meiosis

A type of cell division that reduces the chromosome number by half, producing four haploid cells.

Gametes

Reproductive cells (sperm and eggs) that are haploid and fuse during fertilization.

Diploid

A cell or organism that has two sets of chromosomes, one from each parent.

Haploid

A cell or organism that has a single set of chromosomes.

Chromosomal locus

The specific physical location of a gene on a chromosome.

Crossing over

The process during prophase I of meiosis where homologous chromosomes exchange genetic material.

Genetic variation

Diversity in gene frequencies, important for evolution and adapting to changing environments.

Independent assortment

The process by which different genes independently separate from one another when reproductive cells develop.

Non-disjunction

An error in meiosis or mitosis when homologous chromosomes or sister chromatids fail to separate properly.

Asexual reproduction

A mode of reproduction involving a single parent that produces clones without the fusion of gametes.

Sexual reproduction

A mode of reproduction involving two parents that results in offspring with genetic contributions from both.

Cohesins

Proteins that hold sister chromatids together until they are separated during cell division.

Sporophyte

The diploid phase of the plant life cycle that produces spores through meiosis.

Gametophyte

The haploid phase of the plant life cycle that produces gametes.

Mutations

Changes in the DNA sequence that can lead to variations in inherited traits.

Alleles

Different versions of a gene that can produce different traits.

Zygote

A fertilized egg that results from the fusion of gametes.

Nucleotide excision repair

A DNA repair mechanism that removes and replaces damaged sections of DNA.

Telomeres

Special nucleotide sequences at the ends of eukaryotic chromosomes that protect them from deterioration.

Barr body

An inactivated X chromosome in a female mammal.

Polypeptide

A chain of amino acids that makes up a protein.

Exons

Coding regions of a gene that are expressed in the final mRNA product.

Introns

Non-coding regions of a gene that are spliced out before translation.

Transcription

The process of synthesizing RNA from a DNA template.

Translation

The process of synthesizing a protein from mRNA.

Natural selection

The process by which individuals with favorable traits are more likely to survive and reproduce.

Homologous structures

Anatomical features in different species with similar structure and origin that indicate common ancestry.

Convergent evolution

The independent evolution of similar features in species from different evolutionary backgrounds.

Endemic species

Species that are not found anywhere else in the world and are typically specific to a particular location.

Gene expression

The process by which information from a gene is used to synthesize a functional gene product, often a protein.

Phenotype

The observable traits or characteristics of an organism.

Genotype

The genetic constitution of an organism, represented by its alleles.

Plasmids

Small, circular DNA molecules found in bacteria that are used in genetic engineering.

Cloning

The process of producing similar populations of genetically identical individuals.

Speciation

The process by which new distinct species arise.