Developmental Bio Vocab Flashcards
development
process of progressive and continuous growth generating complex multicellular organisms from single cell
organogenesis
formation of specialized tissues and structures from the 3 germ layers
blastomere
cleavage stage cell resulting from mitosis in an early embryo
blastula
embryonic stage composed of blastomeres
blastocyst
mammalian blastula
blastocoel
cavity within a blastula
embryo
developing organism prior to birth/hatching in humans, early stages of development (fertilization- 8 weeks)
embryogenesis
stages of development between fertilization and birth
gastrulation
formation of 3 germ layers through movement of blastomeres
morphogenesis
creation of ordered form, involves coordinating cell growth, cell migration, and cell death
zygote
diploid egg cell that has been fertilized
indeterminate growth
growth that does not stop, common in plants
oviparity
young hatch from eggs (birds, amphibians, and most invertebrates)
viviparity
young are nourished and born from mother’s body (placental mammals)
ovoviviparity
young hatch from eggs help within mother’s body where they continue to develop for some time (sharks and some reptiles)
pronuclei
egg or sperm, haploid nuclei, form the diploid nucleus of zygote when together
larval/maturity stage
metamorphosis and growth, develop until sexual maturity
gametogenesis
formation of gametes
holoblastic cleavage
yolk is distributed throughout, entire cell is divided into successively smaller cells
meroblastic cleavage
yolk is the dense and only the portion of the egg destined to be the embryo divides
vegetal pole
yolk rich area of embryo
animal pole
side of cell with less yolk
cell movements during gastrulation
invagination, involution, ingression, delamination, and epiboly
invagination
infolding of a sheet (epithelium) of cells, like pushing in a rubberband that is laying on a table
involution
inward movement of an expanding outer layer so that it spreads over the internal surface of the remaining external cells
ingression
migration of individual cells from the surface into the embryo’s interior. Individual cells become mesenchymal and migrate independently
delamination
splitting of one cellular sheet into two parallel sheets resulting in the formation of a new sheet of cells
epiboly
outer surface spreading over inner surface
Differentiation
Diversification/specialization of cell type
Cleavage
Formation of blastomeres from mitosis in early embryo
Fertilization
Joining of haploid gametes to create a new diploid organism
Dorsal blastopore lip
ring formed that opens for movement of endoderm and mesoderm cells through it. ectoderm cells encapsulate the embryo
dorsal
view along the back of the embryo
ventral
view from the eventual stomach, front of organism
ectoderm
outermost germ layer; will eventually give rise to cells of the skin (epidermis), and brain (CNS)
mesoderm
middle germ layer; will eventually give rise to the blood, heart, kidney, gonads, bones, muscles, and connective tissues
endoderm
inner most germ layer; produces stomach cells, thyroid cells, and lung cells