LESSON 1&2 (not Finished) (base On The Pdf) Flashcards
knowledge of facial and _________ and development, hep to treat early malocclusion through prevention, interception, or early correction of interferences
with normal development that lead to malocclusion
somatic growth
A progressive development
Growth
state of going through natural growth, differentiation or evolution through successive changes
Development
the emergence of personal characteristics or features through a growth process; attainment of adult function and size due to proliferation, differentiation, and morphogenesis
Maturation
the growth of different organs or parts at different rates
Differential Growth
DEVELOPMENT PROCESSES OF AN EMBRYO
Induction
Proliferation
Differentiation
Morphogenesis
Maturation
action of one group of cells on another that leads to the developmental pathway in the responding tissue; interaction between developing embryonic cells
Induction
cellular growth; mitosis
Proliferation
change in identical embryonic cells to become structurally and functionally distinct; process of specialization of embryonic cells
Differentiation
development of specific tissue structure or differing form due to cell migration and induction
Morphogenesis
attainment of adult function and size; emergence of personal characteristics or features through a growth process
Maturation
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ from fertilization to implantation
Period of the Ovum
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ 0-1 week
Period of the Ovum
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ 2-8 weeks
Period of the Embryo
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ largely cellular proliferation and migration
Period of the Embryo
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ differentiation of all major internal and external
organs (morphogenesis)
Period of the Embryo
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ very vulnerable stage
Period of the Embryo
PERIODS OF PRENATAL HUMAN DEVELOPMENT
→ 8 weeks to 9 months
Period of the Fetus
PERIODS OF PRENATAL HUMAN DEVELOPMENT
maturation of existing structures
Period of the Fetus
PERIOD OF THE OVUM another term
PRE-IMPLANTATION PERIOD
0 TO 3 DAYS
PERIOD OF THE OVUM (PRE-IMPLANTATION PERIOD)
During 0 TO 3 DAYS there’s a formation of zygote (spermatozoon fertilizes an oocyte) in the oviduct (ampulla of the uterine duct)
PERIOD OF THE OVUM (PRE-IMPLANTATION PERIOD)
zygote undergoes cleavage (series of mitotic divisions as the zygote moves along the uterine tube to the uterus) to form blastomeres
At what day also?
PERIOD OF THE OVUM (PRE-IMPLANTATION PERIOD)
0 TO 3 DAYS
formation of the morula which enters the uterus 3 days after fertilization
PERIOD OF THE OVUM (PRE-IMPLANTATION PERIOD)
formation of the blastocyst (a morula with a fluid-filled space called blastocyst cavity or blastocele)
PERIOD OF THE OVUM (PRE-IMPLANTATION PERIOD)
During these day
implantation
o blastocyst adheres to the surface of the endometrium
AT 6 DAYS
PERIOD OF THE OVUM (PRE-IMPLANTATION PERIOD)
formation of (2) cells from the blastocyst
Trophoblast
Embryoblast
→ outer cell mass
→ single layer of cells covering the outer
portion of the blastocyst
Trophoblast
→ develops into the placenta and other
peripheral structures associated with the embryo
Trophoblast
→ inner cell mass
→ group of cells inside the trophoblast that
develops into the embryo
Embryoblast
period of organogenesis
o 1/100 to 4/100 inch
“week of the two’s”; bilaminar disk stage
PERIOD OF THE EMBRYO (EMBRYONIC PERIOD)
formation of (2) layers from the trophoblast:
Syncytiotrophoblast
Cytotrophoblast
inner multinucleated cells
Cytotrophoblast
→ outer multinucleated cells
→ invades endometrial tissue and
erodes capillaries causing maternal blood to flow into cavities within the _____
syncytiotrophoblast
formation of a bilaminar disk from the embryoblast:
Hypoblast
Epiblast
[[[[[[[PERIOD OF THE EMBRYO (EMBRYONIC PERIOD)]]]]]
squamous or cuboidal cells adjacent to the blastocyst cavity
Hypoblast
→ later known as the primitive yolk sac
→ primitive endoderm
Hypoblast
columnar cells that is separated from the cytotrophoblast by space called amniotic cavity, primitive ectoderm
Epiblast
trilaminar disk stage
THIRD WEEK OF EMBRYONIC DEVELOPMENT
→ gastrulation (the bilaminar disk is converted into a trilaminar
disk)
THIRD WEEK OF EMBRYONIC DEVELOPMENT
period of the “three’s”
o formation of the (3) embryonic or germ layers
o formation of the primitive streak, notochord, and neural
tube
THIRD WEEK OF EMBRYONIC DEVELOPMENT
begins when the primitive streak is formed; its formation will cause the disk to have right and left half wherein each half will be a mirror of the other
TRILAMINAR DISK
a narrow trough with slightly bulging sides that develops in the midline of the epiblast toward the caudal end; develops when ectodermal cells along the central axis proliferate to form a rounded elevation that later becomes a linear structure
Primitive Streak
located at the cranial end of the primitive streak
Primitive Pit
elevated portion around the primitive pit; mesodermal cells that will form the notochord
Primitive Node
movement or migration of cells to the primitive streak and primitive node which detach from the epiblast and continues to grow beneath the epiblast
INVAGINATION
innermost layer composed of cells that displace the hypoblast
Endoderm
composed of cells between the endoderm and the epiblast; formed by the movement of some cells of the epiblast toward the hypoblast at the primitive streak
Mesoderm
composed o the remaining cells of the epiblast
Ectoderm
cells that invaginate into the primitive streak and node grows cranially to form a cellular rod called the ___________ that runs longitudinally in the midline of the trilaminar disk
notochordal process
→ represents the early midline of the embryo where the axial skeleton will form
→ future site of the vertebral column
NOTOCHORD
At the end of the third week, the total length is ______
1.0 mm
> 5mm
> embryo begins to form a tubular structure
FOURTH WEEK OF EMBRYONIC DEVELOPMENT
in front of the primitive streak is the _____
primitive node
mesodermal cells that will form the notochord
primitive node
a neural plate forms
neuroectoderm
also have differentiation of cells from the ectoderm to form the _____
neuroectoderm
At the end of the third week, the total length is.
1.0 mm
embryo folds along this tube–results from extensive proliferation of the ectoderm and the differentiation of specific tissues at the cephalic end
What week?
FOURTH WEEK OF EMBRYONIC DEVELOPMENT
folding results in the formation of the primitive oral
cavity
stomodeum
development of a head fold
What week?
FOURTH WEEK OF EMBRYONIC DEVELOPMENT
head formation
- rostral or head fold
- anterior portion of the neural tube expands as the forebrain, midbrain, and hindbrain
What week?
FOURTH WEEK OF EMBRYONIC DEVELOPMENT
→ process of the development of the neural tube from the closure of the neural plate and neural fold
NEURULATION
→ day18
→ occurs when the notochord and adjacent mesenchyme causes the
ectoderm to form the neural plate
→ mesodermal cells that will form the notochord
NEURULATION
thickening of the ectoderm over the notochord that will fold to form the neural groove
Neural Plate
cells of the neural plate
Neuroectoderm
elevated lateral edges of the neural plate; form the cells of the neural crest
Neural Folds
→ cells from the neural folds
→ migratory (migrates throughout the
body and differentiates into various
structures)
→ population of cells
Neural Crest Cells
multipotent
Neural Crest Cells
gives rise to ectodermal tissues and
mesenchyme in specific areas of the head/face
Neural Crest Cells
provides the embryonic connective tissue needed for craniofacial development (face, neck, and oral tissues)
Neural Crest Cells
a groove located between the neural folds
that fuses to form the neural tube
Neural Groove