Chapter 16 Vocab Flashcards
Differentiation
The process by which a cell or group of cells becomes specialized in structure and function.
Model Organism
A particular species chosen for research into broad biological principles because it is representative of a larger group and usually easy to grow in a lab.
Morphogenesis
The development of the form of an organism and its structures.
Cytoplasmic Determinant
A maternal substance, such as a protein or RNA, that when placed into an egg influences the course of early development by regulating the expression of genes that affect the developmental fate of cells.
Induction
The process in which one group of embryonic cells influences the development of another, usually by causing changes in gene expression.
Determination
The progressive restriction of developmental potential whereby the possible fate of each cell becomes more limited as an embryo develops. At the end of determination, a cell is committed to its fate.
Apoptosis
A type of programmed cell death that is brought about by activation of enzymes that break down many chemical components in the cell.
Pattern Formation
The development of a multicellular organism’s spatial organization, the arrangement of organs and tissues in their characteristic places in three-dimensional space.
Positional Information
Molecular cues that control pattern formation in an animal or plant embryonic structure by indicating a cell’s location relative to the organism’s body axes. These cues elicit a response by genes that regulate development.
Homeotic Gene
Any of the master regulatory genes that control placement and spatial organization of body parts in animals, plants, and fungi by controlling the developmental fate of groups of cells.
Embryonic Lethal
A mutation with a phenotype leading to death of an embryo or larva.
Maternal Effect Gene
A gene that, when mutant in the mother, results in a mutant phenotype in the offspring, regardless of the offspring’s genotype. Maternal effect genes, also called egg-polarity genes, were first identified in Drosophila melanogaster.
Egg Polarity Gene
A gene that helps control the orientation (polarity) of the egg; also called a maternal effect gene.
Bicoid
A maternal effect gene that codes for a protein responsible for specifying the anterior end in Drosophila melanogaster.
Morphogen
A substance, such as Bicoid protein in Drosophila, that provides positional information in the form of a concentration gradient along an embryonic axis.
Totipotent
Describing a cell that can give rise to all parts of the embryo and adult, as well as extraembryonic membranes in species that have them.
Stem cell
Any relatively unspecialized cell that can produce, during a single division, one identical daughter cell and one more specialized daughter cell that can undergo further differentiation.
Pluripotent
Describing a cell that can give rise to many, but not all, parts of an organism.
Oncogene
A gene found in viral or cellular genomes that is involved in triggering molecular events that can lead to cancer.
Proto-oncogene
A normal cellular gene that has the potential to become an oncogene.
Tumor suppressor gene
A gene whose protein product inhibits cell division, thereby preventing the uncontrolled cell growth that contributes to cancer.
Ras gene
A gene that codes for Ras, a G protein that relays a growth signal from a growth factor receptor on the plasma membrane to a cascade of protein kinases, ultimately resulting in stimulation of the cell cycle.
P53 gene
A tumor-suppressor gene that codes for a specific transcription factor that promotes the synthesis of proteins that inhibit the cell cycle.
