Term
| does the second meiotic division of meiosis have a normal interphase? why or why not? |
|
Definition
| no, it does not have a normal interphase because there is no DNA replication; 1n --> 1n |
|
|
Term
| middle piece of the tail of a sperm |
|
Definition
| contains a helical arrangement of the mitochondria, which provide adenosine triphosphate necessary for activity |
|
|
Term
| which gene/molecular factor is associated with maturation of germ cells? |
|
Definition
| proteins of the Bcl-2 family |
|
|
Term
| oocyte maturation inhibitor |
|
Definition
| believed to be released by follicular epithelial cells; keeps the meiotic process of the primary ooctye arrested |
|
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Term
|
Definition
zona pellucida and a layer of follicular epithelial cells
surrounds the oocyte |
|
|
Term
| which structures in the oocyte provide nutrition to the dividing zygote during the first week of development? |
|
Definition
|
|
Term
three layers of the endometrium
which is considered the functional layer? |
|
Definition
1. compact layer = dense CT
2. spongy layer = edematous CT
3. basal layer = contains blind ends to uterine glands
**compact + spongy layers = functional layer |
|
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Term
| gonadotropin-releasing hormone (females) |
|
Definition
made in hypothalamus --> to anterior pituitary
stimulate the release of FSH and LH (from anterior pituitary) |
|
|
Term
|
Definition
from anterior pituitary
stimulates development of ovarian follicles and production of estrogen by follicular cells |
|
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Term
|
Definition
"trigger" for ovulation
stimulates the follicular cells and corpus leutum to produce progesterone |
|
|
Term
| what do thecal cells release? |
|
Definition
| angiogenesis factor = promotes growth of blood vessels in the theca interna that provide nutritive support for follicular development |
|
|
Term
|
Definition
| a mound of follicular cells that project into the antrum |
|
|
Term
|
Definition
| an ovulatory agent; stimulates the release of pituitary gonadotropins (FSH and LH) |
|
|
Term
|
Definition
| when there is no ovulation and no corpus leutum forms. This causes the proliferative phase to continue until menstruation to begin because LH and FSH are not released as normal (estrogen works on hypothalamus and pituitary to prevent this). Seen in women who are on oral contraceptives |
|
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Term
|
Definition
| an enzyme produced by the seminal glands and is found in ejaculate that coagulates some of the semen to form a vaginal plug to prevent back flow of the semen into the vagina |
|
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Term
| which enzymes initiate and facilitate the acrosome reaction? |
|
Definition
| hyaluronidase and acrosin (released from the acrosome of the sperm) |
|
|
Term
|
Definition
| two sperms that fertilize the same egg = results in triploid conceptions |
|
|
Term
| which enzymes help the sperm pass through the corona radiata of the oocyte? |
|
Definition
hyalouronidase from acrosome of the sperm
tubal mucosal enzymes of the female |
|
|
Term
| which enzymes help the sperm pass through the zona pellucida? |
|
Definition
acrosin** (proteolytic enzyme = most important)
esterases
neuraminidase |
|
|
Term
| what makes up the chorion? |
|
Definition
extraembryonic somatic mesoderm and the two layers of the trophoblast
**forms the wall of the chorionic sac |
|
|
Term
| by the middle of the third week, the intraembryonic mesodern separates the ectoderm and endoderm everywhere except: |
|
Definition
oropharyngeal membrane
median plane of cranial to the primitive node
cloacal membrane |
|
|
Term
| function of the notochord |
|
Definition
defines primordial longitudinal axis of embryo and provides rigidity
provides signals that are necessary for the development of muscles and CNS
contributes to the intervertebral discs |
|
|
Term
| which are older, caudal or cranial somites? |
|
Definition
|
|
Term
| which genes and signaling factors contribute to the formation of somites from paraxial mesoderm? |
|
Definition
Notch pathway genes
Hox genes
Fox C1 and C2
Delta-Notch signaling system (craniocaudual segmental pattern) |
|
|
Term
| when does hematogenesis (blood formation) start in the embryo? |
|
Definition
|
|
Term
| three phases of human development |
|
Definition
1. growth (cell growth)
2. morphogenesis (development of body shape, size and organs)
3. differentiation (maturation of physiological processes) |
|
|
Term
| what is formed from the septum transversum? |
|
Definition
| central tendon of the diaphragm |
|
|
Term
| from where does the foregut arise and what does it produce? |
|
Definition
from the endoderm (lies between the brain and heart in folded embryo)
primordium of pharynx, esophagus, etc. |
|
|
Term
| from where does the hindgut derive? |
|
Definition
| endodermal germ layer (in the tail fold) |
|
|
Term
|
Definition
terminal part of the hind gut in the tail fold of the embryo
primordium of the urinary bladder and rectum |
|
|
Term
| what is the position of the primitive streak in relation to the cloacal membrane before and after folding? |
|
Definition
before folding = primitive streak is cranial to cloacal membrane
after folding = caudal to cloacal membrane |
|
|
Term
| what produces the lateral folding of the embryo? |
|
Definition
| rapidly growing spinal cord and somites |
|
|
Term
| from where does the midgut derive? |
|
Definition
| from the lateral folding of the endodermal germ layer |
|
|
Term
|
Definition
| reduced connection between the midgut and the umbilical vesicle after lateral folding |
|
|
Term
| what forms the epithelial covering of the umbilical cord? |
|
Definition
|
|
Term
| three mechanisms of signal transfer in induction |
|
Definition
1. diffusible molecules
2. matrix-mediated interaction (non-diffusible extracellular matrix)
3. cell contact |
|
|
Term
| from where does the specificity of induction arise? |
|
Definition
| From the reacting tissue and not from the inductor |
|
|
Term
| inductive systems have which common feature? |
|
Definition
| close proximity between the interacting tissues |
|
|
Term
|
Definition
| scanty menstruation (can contribute to unreliable LNMP when determining gestational age) |
|
|
Term
|
Definition
| dating pregnancy from the last normal menstrual period (LNMP) |
|
|
Term
| which measurement is calculated most frequently to determine embryonic age? |
|
Definition
|
|
Term
| which main type of tissue comes from the endoderm? Which areas of the body specifically? |
|
Definition
epithelium/epithelial parts:
- respiratory tract
- GI, liver pancreas and urinary bladder
- ear, nose and throat |
|
|
Term
| What arises from the endoderm? |
|
Definition
epithelial parts of:
trachea
bronchi
lungs
pharynx
thyroid gland
tympanic cavity
pharyngotympanic tube
tonsils
parathyroid gland
epithelium of:
GI tract
liver
pancreas
urinary bladder
urachus |
|
|
Term
| what are the four types of mesoderm that develop? |
|
Definition
head
paraxial
intermediate
lateral |
|
|
Term
| what is derived from the head mesoderm? |
|
Definition
|
|
Term
| what is derived from the paraxial mesoderm? |
|
Definition
muscles of head
striated skeletal muscle (trunks, limbs)
skeleton (except cranium)
dermis of skin
CTs |
|
|
Term
| what is derived from the intermediate mesoderm? |
|
Definition
urogenital system
Gonads
ducts
accessory glands |
|
|
Term
| What is derived from the lateral mesoderm? |
|
Definition
CT and muscle of viscera
serous memebranes of pleura, pericardum and peritoneum
primordial heart
blood and lymphatic cells
spleen
suprarenal (adrenal) cortex |
|
|
Term
| what are the two type of ectoderms that arise from the embryonic ectoderm? |
|
Definition
surface ectoderm
neuroectoderm |
|
|
Term
| what is derived from the surface ectoderm? |
|
Definition
epidermis
hair
nails
cutaneous and mammary glands
anterior pituitary gland
enamel of teeth
internal ear
lens of eye |
|
|
Term
| the neuroectoderm makes up which two main embryonic structures? |
|
Definition
|
|
Term
| what is derived from the neural crest? |
|
Definition
cranial and sensory ganglia and nerves
medulla of adrenal gland
pigment cells
pharyngeal arch cartilages
head mesenchyme and CT
bulbar and conal ridges in heart |
|
|
Term
| what is derived from the neural tube? |
|
Definition
CNS
retina
pineal body
posterior pituitary |
|
|
Term
| at what birth weight are fetuses considered premature infants? |
|
Definition
|
|
Term
| at what birth weight are fetuses considered immature infants? |
|
Definition
| less than 500g (and up to 1500?) |
|
|
Term
| can insulin pass the placental membrane? |
|
Definition
| no, but is believed to stimulate fetal growth |
|
|
Term
| intrauterine growth restriction (IUGR) |
|
Definition
| process that causes reduction in expected pattern of fetal growth and decreased birth weight |
|
|
Term
|
Definition
cigarette smoking
multiple pregnancies
alcohol and illicit drugs
impaired uteroplacental and fetoplacental blood flow
genetic factors and growth retardation |
|
|
Term
|
Definition
| branch of medicine that is concerned with the well-being of the fetus and newborn infant (combines obstetrics and pediatrics) |
|
|
Term
|
Definition
| invasive prenatal diagnostic procedure performed at 15-18 weeks; usually tests for genetic disorders |
|
|
Term
|
Definition
| alpha fetoprotein is a glycoprotein synthesized in fetal liver, umbilical vesicle and gut; levels are high in CNS anomalies or open neural tube defects; low in fetuses with down syndrome or trisomy 18 |
|
|
Term
| spectrophotometric studies |
|
Definition
| asses degree of erythroblastosis fetalis (hemolytic diseases)= destruction of fetal RBCs by maternal antibodies |
|
|
Term
| chorionic villus sampling |
|
Definition
biopsies of trophoblastic tissues; used to detect chromosomal abnormalities, inborn errors of metabolism and x-linked disorders
performed between 10-12 weeks
risk of miscarriage = 1% (>than in amniocentesis) |
|
|
Term
|
Definition
| can detect fetal sex from amnionotic fluid |
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