HLTH 310 Test 2 Flashcards
Two layers of the embryonic disc
epiblast, hypoblast
Trophoblast forms
cytotrophoblast, syncytiotrophoblast, chorion
Go through diagram of all of these
Cytotrophoblast
outside layer
stick to endometrium and burrow through uterine wall
attract maternal blood vessels
syncytiotrophoblast
multinucleated body that digests uterine tissue
chorion
embryonic contribution to placenta
membrane that surrounds all others
Amniotic cavity filled with
amniotic fluid
What does amniotic fluid help with
cushion shock absorber
regulate temperature
Yolk Sac
helps with blood circulation, supplies some nutrients than placenta takes over
Cells migrate through primitive streak and form two layers
first layer, endoderm
second layer, mesoderm
cells of epiblast that did not migrate through are ectoderm
gastrulation form
three germ layers
endoderm, mesoderm, ectoderm
Maternal portion of placenta
decidua basalis
Functions of the placenta
Nutrition and digestion, respiration, endocrine
Identical, monozygotic twins
single zygote
fraternal dizygotic twins
two different zygotes
identical twins
share chorion, separate amnion
Placenta Previa
When the placenta is in the way of the cervix
Endoderm
Internal organs
digestive system
liver
pancreas
lungs
Mesoderm
Other stuff
dermis of skin
lung tissue
circulatory system
muscle systems
Ectoderm
outside things
epidermis of skin
hair
nails
CNS nervous system
fourth germ layer
neural crest, PNS
Umbilical arteries carry
deoxygenated blood
Umbilical single vein carries
oxygenated blood
Neurulation
formation of the neural tube
Somitogenesis
mesodermal cells in developing truck segmentation
Notochord
signals the ectoderm to thicken and form neural plate
Neural plate border do what
come together, then the neural tube disconnects
When neural tube disconnects what frees
the neural crest becomes free which becomes the PNS
The notochord degenerates at the end of neurulation and only persists as
the nucleus pulposus
Neural tube defects can come from deficiency of what
folic acid
Spina bifida
Ball at bottom of spine, failure of posterior nueropore closure
Anencephaly
near top of head, failure of closure of anterior neuropore closure
Primitive streak starts the folding, causes mesoderm to create and continues folding
Formation of circulatory system
first system made, heart starts beating at 4 weeks, mesodermal cells create the circulatory system
What gene on y chromosome develops testes
SRY gene
Women duct
Mullerian
Male duct
Wolffian
What cells produce female Mullerian
no cells, no sertoli and no leydig
What cells produce male Wolffian
need sertoli cells to produce MIS to kill mullerian, need leydig cells to make testosterone to make testes
Androgen insensitivity
Where you do not have any internal genetalia
develop testes, then develop female like external genetalia
5 alpha reductase
develop internal male genetalia
hypospadias which creates female like external genetalia cause of lack of prostate growth
Ductus venosus
lets blood bypass the immature liver
Ductus arteriosus
lets blood bypass the immature lungs
Foramen ovale
lets blood go from right atrium to left atrium
Weeks 9-12
end of first trimester
uncontrolled movements
major neuronal proliferation starts
bone marrow takes over RBC making
Weeks 13-16
beginning of second trimester
neuronal migration starts
meconium accumulates in intestines
meconium
fetus can inhale their fecus
causes amniotic fluid to be greenish/yellow
Weeks 16-20
silky lanugo hair appears
fetal position due to space restriction
fetal movements
coat skin with waxy vernix caseosa
Weeks 21-30
myelination of axons in spinal cord beings
lungs start to produce surfactant
Weeks 31-birth
shedding of lanugo hair
fetus lays down subcutaneous fat
Rubella
respiratory disease, can develop into congenital rubella syndrome
genetic and environmental interactions
certain mice with certain DNA developed cleft palate when exposed
Thalidomide
missing limbs, phocomelia and amelia
Causes of birth defects
- inheritance, genes and environment
- familial conditions
- chromosomal issues
- teratogens
- dominant or recessive gene
Development disorders
cleft palate, cleft lip, heart defects, spina bifida or anecephaly, malformation in limbs, extra fingers and toes, hypospadia
Teratogens
cross the placenta, cause congenital malformations
principles of teratology
dose and duration of exposure
what type is the teratogen
development stage at time of exposure
genotype of the embryo
neural defects can happen
all the time of pregnancy
Earlier systems/things affected
upper and lower limbs, heart, upper lip
Later systems/ things affected
senses, hearing, eyes, teeth, palate, external genital
Prenatal exposure that have affects on brain and body
recreational drugs- alcohol and smoking
prescription drugs
illegal hard drugs- cocaine
mercury
heavy metals
Mercury contamination
prenatally exposed children caused issues
CNS impairments
in food chain, mercury in water, fish, humans eat fish
Anticonvulsants
for seizures mother take them, cause baby to have severe defects, neural, facial, and liver defects
What does alcohol cause as a teratogen
behavioural defects, cognitive, facial defects
illegal drugs teratogens
dont cause physical defects but cause cognitive, IQ reduction, behavioural
congenital heart defects
most common class of birth defect
can defect heart valves, atrium and ventricles, arteries and veins
Maternal serum
screening, have alpha-fetoprotein- test for tubule defects, and multiple analyte screens- test for aneuplodies
Maternal blood
screening, cell-free fetal DNA, test for aneuplodies
Chorionic villi
diagnostic, karyotype DNA testing,enzyhme hormonal, abnormal screening test for a specific genetic disorder
Amniotic fluid
diagnostic, karyotype DNA testing, abnormal screening test for a specific genetic disorder
Fetal blood
diagnostic, karyotype DNA testing, abnormal screening test for a specific genetic disorder
Nuchal Translucency
test to show aneuplodies, isnt for sure testing
Maternal serum- alpha-fetoprotein
AFP is from fetal liver and secreted by fetal urine
measured in first and second trimester
Chorionic villus sampling
goes through mother cervix, takes placental tissue
Amniotic fluid sampling, amniocentesis
goes through mothers abdomen, takes fetal cells, centrifuge
Fetal heart surgery
surgeon goes into heart through abdomen and uterine wall where the valve is blocked, takes a balloon in then blows up balloon which pops open the valve
Full term in weeks
38.5 weeks from conception
40.5 weeks from last period
Progesterone during pregnancy
ovulation prevention, inhibits contractions
Relaxin in pregnancy
increases elasticity in joints and ligaments in pelvis
hCG in pregnancy
stimulate testosterone in male
estrogen in pregnancy
stimulates growth of uterus and mammalary glands
Gestational diabetes
pregnancy hormones cause insulin resistance, increased risk of pre-term labor or development of type two diabetes
Pre-eclampsia
protein in urine, high blood pressure
liver and kidney damage, bleeding, fetal growth restriction
if not treated, coma, seizure
Stimulation of uterine contractions
oxytocin and prostaglandins
Expulsion stage, birth
position of fetus affects this stage
tearing between vagina and anus, perineum
presentation of newborn head
breach position
legs come out first
Cervical dilation
each time contraction, no oxygen to baby
amniotic fluid burst, look for yellow/ greenish colour for meconium
longest stage of labor
oxytocin to make contractions
full 10cm diameter
Afterbirth
placenta comes out after baby
contractions to reduce blood loss
C-section
baby removed through abdomen, surgical procedure
unusual position, placenta previa, pre-eclamsia, STI
Respiratory adjustments at birth
constriction of the umbilical vein, low oxygen and high carbon, acidosis causes the respiratory part in brain to work
first breathe in 10 seconds of birth
Circulatory adjustments, shunts close
The shunts become ligaments
clamping of umbilical cord
doctor clamps it, will also happen on its own
collapsed vessels become ligaments
ductus venosus after birth becomes…
ligamentum venosum
foramen ovale after birth becomes
fossa ovalis
ductus arteriosus after birth becomes…
ligamentum arteriosum
Thermoregulatory adjustments
mitochondrial cells produce heat and less ATP
babies can’t shiver to warm themselves
produce heat slower and lose it faster
lots of capillaries, breakdown brown fat
APGAR test
Appearance - blue or not
Pulse - normal pulse, more than 100
Grimace - sneeze, cough, pull away when stimulated
Activity - can move around
Respiration - strong breathe or not
Hyperplasia
growth in number of cells, cell division
hypertrophy
growth in size of cell, no cell division
Accretionary growth
growth in ECM between cells
Appositional
hyperplasia and accretionary growth in surface of tissue
Interstitial
hyperplasia and accretionary growth throughout thickness of tissue
Neurons growth
Born with a set amount of neurons, but synapses can increase
Bone formation
bone is put down after a cartilage template
by birth most cartilage is replaced with bone
two types of ossification
intramembranous
endochondral
Intramembranous
spongey bone
flat bones of face
at birth skull not fully ossified yet
Endochondral ossification
bone develops by replacing hyaline cartilage
start with formation of cartilage
mesenchymal cells differentiate into chondroblasts which develop into chondrocytes
Osteogeneic cells
develop into osteoblasts
Osteoblasts
bone formation
Osteocytes
help with mineral concentration of matrix
Osteoclasts
bone breakers
Diaphysis
middle of bone, shaft
Metaphysis
flared end of shaft
epiphysis
the end of the bone, the growth plate
Osteoblasts secrete bone tissue onto the
calcified cartilage matrix (Ossification)
Bone modelling
deposition of new bone beneath periosteum, and reabsorption of old bone that lines the medullary cavity
Bone remodelling
resorption of old or damaged bone on same surface where new bone is made
Exercise on bone
weight bearing helps bone minerals and collagen fibres
resistance helps with, slow down bone loss
growth hormone affects at
epiphyseal plate
stimulate hypertrophy and hyperplasia
