Powerpoint 4 Flashcards
what is the sequence for the embryology of neural tube development?
- Neurulation
- Neural Plate
- Neural tube
- Central nervous System
during neuralation, what is created?
the neural plate
What step of neural tube development occurs during the 3rd-4th week of gestation?
neurulation
Which step of neural tube development forms the actual neural tube?
the neural plate
The neural tube differentiates into the ___
CNS
What are the four hormones that drive histological changes in the ovary and uterus?
- FSH
- LH
- Estrogen
- Progesterone
What do you call an embryo that is after fertilization and before the first cell division?
A Zygote
What is the noncellular membrane that is formed around the primary oocyte called?
zona pellucida
What are the stages of development for the early embryo?
- Zygote stage
- Morula stage
- Blastocyst stage
- Implantation
What does the trophoblast layer of the blastocyst lead to the formation of?
The placenta
What does the inner cell mass in the blastocyst turn into?
the embryo
True or False:
the inner cell mass will never orient itself to be on the side nearest the endometrium.
False! It will ALWAYS orient itself to be near the endometrium
What is known as a specific protein on trophoblast cells that binds to carbohydrate receptors on uterine epithelium (endometrium) to mediate the initial attachment of blastocyst to uterine epithelium?
L-selectin
does in the inner cell mass differentiate into a bilaminar or trilaminar embryonic disc?
Bilaminar
What are the names of the two layers of the ICM embryonic disc?
Epiblast layer and Hypoblast layer
Gastrulation is the process during embryonic development that changes the embryo from a ________ to a ________ by the inward migration of cells
blastula, gastrula
What 4 things occur during Gastulation?
- Bilaminar embryo –> trilaminar embryo
- the three germ layers are formed
- Formation of primitive streak
- formation of notochord
What are the three germ layers?
- ectoderm
- endoderm
- mesoderm
What is responsible for organizing the embryonic axis?
the primitive streak
By the end of the ____ week of gastrulation, the bilaminar disc is formed
2nd
the somite will develop into vertebrae and form from which germ layer?
mesoderm
What establishes the longitudinal or craniocaudal axis, and the left and right sides of the developing embryo?
primitive streak
What germ layer is the neural plate’s origin?
ectoderm
What is a midline mesodermal rod of tissue running craniocaudal in a developing embryo, between ectoderm and endoderm
Notochord
Paraxial mesoderm definition
mesoderm on both sides of the notochord
Notochord + paraxial mesoderm —> induces formation of _______ ______
neural plate
Endoderm (internal layer) involves what?
- lung cells
- thyroid cells
-digestive cells - epithelial lining of the digestive tube
- forms lining of glands
The ectoderm layer (external layer) involves what?
- skin cells of epidermis
- neurons in the brain
- pigment cells
- CNS formation
- spinal cord formation
What are the two important genes involed in neural tube formation?
Shh (sonic hedgehog) and BPMs (bone morphogenetic proteins)
What is the role of the four extraembryonic membranes?
protect the developing embryo
What are the four extraembryonic membranes?
- yolk sac
- amnion
- chorion
- allantois
Which was the first extraembryonic membrane to form?
yolk sac
What extraembryonic membrane is composed of endoderm and mesoderm and connects to the developing gut via the yolk stalk?
yolk sac
What is the innermost extraembryonic membrane layer and is considered to be the MOST IMPORTANT?
Amnion
What is the role of the Amnion layer?
it surrounds the body of the fetus and allows it to be suspended in amniotic fluid and protects it from medicinal harm
What are the germ layers that make up the amnion?
ectoderm and mesoderm
What extraembryonic membrane forms outside the amnion, is composed of ectoderm and mesoderm, participates in placenta formation, and is the outer-most layer?
chorion
What extraembryonic membrane forms as a diverticulum from the hindgut, is composed of endoderm and mesoderm, and participates in placenta formation?
allantois
