Pharyngeal Arches 1 - Herring Flashcards
an important landmark for brain development that sets up the specialization of the cerebral hemispheres (forebrain)
Prechordal plate
What induces overlying ectoderm to differentiate to neuro-ectoderm via neurulation
notochord forming the primordial axis
when does neurulation begin
week 3
how does neurulation begin
with the notochord inducing the overlying ectoderm to form the neural plateon the posterior aspect of the trilaminar embryo by day 18
the neural tube primarily forms the
CNS
the center of the neural tube will form the
ventricular system and central canal of the spinal cord
The first fusion of neural folds in humans occurs at the level of the future ___________ and occurs atday _____
hindbrain-cervical junction
22
The cranial two-thirds of the neural plate and tube represents thefuture ______
brain
Caudal one-third of the neural plate and tube represents the future______
spinal cord(cervical toapproximatelyS2 levels)
Unfused portions at the cranial and caudal ends are referred to as
neuropores
The cranial end of the neural tube forms the _____
brain
Theforebraingives rise to the__________and_________
cerebral hemispheres
diencephalon
the midbrain becomes the
adult midbrain
the hindbrain gives rise to the ____ , ________ , and _________-
pons
cerebellum
medulla
the remainder of the neural tube forms the
spinal cord
Neural crest cells (NCCs) are a unique population of cells that arise from thedorsal part of the
developing neural tube
neural crest cells arise during the process of
neurulation
mesenchyme =
embryonic connective tissue
Neural crest cells migrate to many specific locations in the body and differentiate into a variety of cells that form:
most of the PNS and ANS
dorsal root (spinal) and autonomic system ganglia
sensory ganglia of cranial nerves
pia mater and arachnoid mater
Schwann cells (type of glial cell)
craniofacial bony structures
melanocytes
cells of the suprarenal (adrenal) medulla
Neural crest cells form 2 types of structures in the head:
Ectomesenchyme derivatives and Non-ectomesenchyme derivatives
Ectomesenchyme derivatives forms many of the skeletal and connective tissue components of the head including:
bone, cartilage, connective tissue and dentin
Non-ectomesenchyme Derivatives: what are they?
Neurons and glial cells of the sensory, sympathetic, and parasympathetic nervous system
Melanocytes (pigment-containing cells) of the epidermis
Oropharyngeal (buccopharyngeal) membrane pulled
ventrally
Oropharyngeal (buccopharyngeal) membrane = developing brain becomes most _______ part of the embryo
cranial
an ectoderm pouch located between the future brain & developing heart
stomodeum
what is the future structural formation of the oral cavity
stomodeum
Primordial heart located _____ to the developing brain and oropharyngeal membrane
rostral
Longitudinal folding moves the future heart toward the region of the ______
thorax
On each side (R/L) of the stomodeum, the _______ start to develop
branchial or pharyngeal arches
The primitive oral cavity is surrounded by the ___________ and ___________
first pharyngeal arch
frontonasal prominence
The structural development of the head and neck occurs between weeks ______ of gestation
3-8
The embryonic basis of the head and neck is 5 pairs of _________-
pharyngeal (branchial) arches
the pharyngeal arches form where and when
on either side of the cranial foregut
during late week 3 - early week 5