Zoology Lab quiz 4
A mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
Cell division of a Zygote
An embryo at the stage following the blastula, when it is a hollow cup-shaped structure having three layers of cells.
The rudimentary alimentary cavity of an embryo at the gastrula stage.
The second stage of larval development in many starfishes
A diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.
An animal embryo at the early stage of development when it is a hollow ball of cells.
A phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a trilaminar ("three-layered") structure known as the gastrula.
Each of the three layers of cells (ectoderm, mesoderm, and endoderm) that are formed in the early embryo.
The body cavity in metazoans, located between the intestinal canal and the body wall.
The opening of the central cavity of an embryo in the early stage of development.
The fluid-filled cavity of a blastula.
A cell formed by cleavage of a fertilized ovum.
the innermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the lining of the gut and associated structures.
when the coelom is lined with mesoderm,providing muscle in the gut to power gut motility.
Having a body derived from three embryonic cell layers (ectoderm, mesoderm, and endoderm).
A multicellular organism whose mouth develops from a primary embryonic opening.
Any of a numerous animals, in which the anus develops from the first opening in the embryo and the mouth develops later.
The middle layer of an embryo in early development, between the endoderm and ectoderm.
An invertebrate lacking a coelom
A resistant membranous layer in eggs of many animals that forms following fertilization by the thickening and separation of the vitelline membrane from the cell surface and that prevents multiple fertilization.
The fusion of gametes to initiate the development of a new individual organism
The first stage in the larval development of most starfish
The outermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the epidermis and nerve tissue.
any of a group of invertebrates with a three-layered body that has a fluid-filled body cavity between the endoderm and the mesoderm.