Ch 5: Life History Flashcards
quiz
the process by which cells influence the way adjacent cells respond and regulate their genes
induction
the three components of developmental time during differentiation of cells
restriction (limiting), expression (actual organization property), and determination (exacting)
Cell fates and patterns of interaction and change at the cellular level during embryogenesis
Epigenetics
type of cell organization; Closely packed, polarized cells
on the basal lamina, with junctional
complexes
Epithelial cells
type of cell organization; Stellate, loosely packed cells in
gelatinous extracellular matrix
high in water and protein
Mesenchymal cells
origination and development of the sperm cell
Spermatogenesis
the last phase of spermatogenesis
Spermiogenesis
origination and development of the egg cell
Oogenesis
eggs and sperm are _________; they are the ________ and the _________ respectively
gametes, spermatozoon, oocyte
rapid cell division without cytoplasmic growth
cleavage
process of forming one gastrula layer from three blastula layers
Gastrulation
having little yolk
Microlecithal
having an intermediate amount of yolk
Mesolecithal
having much yolk
Macrolecithal
division process in which the entire zygote divides along cleavage furrows
Holoblastic cleavage
cleavage furrows do not extend into yolk mass
Meroblastic cleavage
multicellular embryo prior to
gastrula stage
Blastula
a cell of the blastula
Blastomere
when no growth occurs
in cleavage and stored energy is
utilized, mass decreases, and a space opens in the embryo. The space is called a __________.
Blastocoele
formation of the neural tube; near the end of gastrulation; somites form
Neurulation
forms the notochord
chordamesoderm
the movement of mesenchymal cells down the primitive streak
Ingression
form the yolk sac endoderm
Hypoblast cells
endoderm and splanchnic mesoderm covered pouch full of nutrients for the developing organism
yolk sac
the formation of folds that line the amniotic cavity and isolate the embryo
Amnion
formed from the upper amniotic folds, lined with mesoderm; forms a general covering
Chorion
the evagination of archenteron that grows into contact with the chorion to form the only vascular membrane
Allantois
modified blastula of a placental mammal; there is no yolk to affect cleavage.
Blastocyst
outer layer of the mammalian blastocyst; initiates placenta formation
Trophoblast
lies between the trophoblast and inner cell mass
Blastocoel
grows ventrally from the yolkless sac
Endodermal yolk sac layer
The three primary embryonic germ layers
ectoderm, mesoderm, endoderm
First layer in ocular organogenesis; differentiates into telencephalon and diencephalon
Prosencephalon
forms metencephalon and myelencephalon; Segmental thickenings called
rhombomeres
Rhombencephalon
mesenchyme
of neural crest origin; neural crest
is formed from ectoderm.
Ectomesenchyme
form components of the
sensory and autonomic nervous
systems
Cranial and Trunk Neural Crest
similarities between embryonic
development across diverse taxa; embryos develop (and lose) structures that characterize ancestral forms (ex. gill slits developing in early reptile,
mammal, and bird embryos; Ontogeny recapitulates phylogeny
Haeckel’s Biogenic Law
Development proceeds from general to specific; Notochord is lost in adult vertebrates, but is an important structural element in the embryo
Von Baer’s Law
older structures exert influence over the development of newer structures
Preservationism
genes can have multiple effects
Pleiotropy
contain highly conserved regions recognizable across a wide variety of multicellular animals; controls axial pattern of development
Hox Genes
