Sea Urchin Development and Drosophila Genetics

These flashcards cover key vocabulary and concepts in Sea Urchin and Drosophila development.

Zygote

The fertilized egg that results from the fusion of an egg and a sperm.

Blastula

An early developmental stage consisting of a hollow ball of cells.

Gastrula

The stage following the blastula, where the embryo begins to form different layers (germ layers).

Micromeres

Small cells located at the vegetal pole of the egg that contribute to mesoderm formation.

Macromeres

Larger cells that contribute to the ectoderm and endoderm of the embryo.

Animal-Vegetal Axis

An axis in the embryo that defines the orientation with the animal pole at the top and the vegetal pole at the bottom.

Oral-Aboral Axis

An axis that denotes the orientation from the mouth (oral) to the opposite end (aboral).

Drosophila

A genus of small flies, commonly known as fruit flies, used as a model organism in genetics and development.

Notch Signaling

A pathway important for cell communication that is crucial for determining cell fate during development.

Dorsal-Ventral Axis

The axis in an embryo that runs from the back (dorsal) to the belly (ventral) and helps in establishing body plan.

Maternal Factors

Proteins and RNAs deposited by the mother into the egg that are crucial for the early stages of development.

Zygotic Genes

Genes that are expressed after fertilization, important for establishing body axes and further development.

Homeotic Genes

Genes that determine the identity of body segments or structures in an organism.

Transcription Factor

Proteins that bind to specific DNA sequences and control the transcription of genetic information from DNA to mRNA.

Gap Genes

A class of zygotic genes that regulate the expression of other genes and establish broad regions in the embryo.

Pair-Rule Genes

Zygotic genes that establish segments in the developing embryo by exhibiting stripe-like expression patterns.

Hox Genes

A group of related genes that control the body plan of an embryo along the head-tail axis.

Auxin Signaling

A hormone-related pathway that regulates plant growth and development.

Gastrulation

The process during embryonic development that rearranges the blastula to form the three germ layers: ectoderm, mesoderm, and endoderm.

Embryogenesis

The process by which a single-celled zygote develops into a multicellular embryo.

Endoderm

The innermost layer of cells in an embryo that gives rise to the gut and internal organs.

Mesoderm

The middle layer of cells in an embryo that gives rise to muscles, the circulatory system, and other internal structures.

Ectoderm

The outermost layer of cells in an embryo that forms the skin and nervous system.