Chapter 16 Vocab

Question 0

Differentiation

Answer 0

The process by which a cell or group of cells becomes specialized in structure and function.

Question 1

Model Organism

Answer 1

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.

Question 2

Morphogenesis

Answer 2

The development of the form of an organism and its structures.

Question 3

Cytoplasmic Determinant

Answer 3

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.

Question 4

Induction

Answer 4

The process in which one group of embryonic cells influences the development of another, usually by causing changes in gene expression.

Question 5

Determination

Answer 5

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.

Question 6

Apoptosis

Answer 6

A type of programmed cell death that is brought about by activation of enzymes that break down many chemical components in the cell.

Question 7

Pattern Formation

Answer 7

The development of a multicellular organism’s spatial organization, the arrangement of organs and tissues in their characteristic places in three-dimensional space.

Question 8

Positional Information

Answer 8

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.

Question 9

Homeotic Gene

Answer 9

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.

Question 10

Embryonic Lethal

Answer 10

A mutation with a phenotype leading to death of an embryo or larva.

Question 11

Maternal Effect Gene

Answer 11

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.

Question 12

Egg Polarity Gene

Answer 12

A gene that helps control the orientation (polarity) of the egg; also called a maternal effect gene.

Question 13

Bicoid

Answer 13

A maternal effect gene that codes for a protein responsible for specifying the anterior end in Drosophila melanogaster.

Question 14

Morphogen

Answer 14

A substance, such as Bicoid protein in Drosophila, that provides positional information in the form of a concentration gradient along an embryonic axis.

Question 15

Totipotent

Answer 15

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.

Question 16

Stem cell

Answer 16

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.

Question 17

Pluripotent

Answer 17

Describing a cell that can give rise to many, but not all, parts of an organism.

Question 18

Oncogene

Answer 18

A gene found in viral or cellular genomes that is involved in triggering molecular events that can lead to cancer.

Question 19

Proto-oncogene

Answer 19

A normal cellular gene that has the potential to become an oncogene.

Question 20

Tumor suppressor gene

Answer 20

A gene whose protein product inhibits cell division, thereby preventing the uncontrolled cell growth that contributes to cancer.

Question 21

Ras gene

Answer 21

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.

Question 22

P53 gene

Answer 22

A tumor-suppressor gene that codes for a specific transcription factor that promotes the synthesis of proteins that inhibit the cell cycle.