Embryogenesis and Development Flashcards
Ampulla
largest part of the fallopian tube, where fertilization occurs
acrosomal apparatus
tubelike structured formed by the secondary oocyte’s membrane when sperm comes into contact. Allows movement of pronucleus into oocyte
cortical reaction
release of Ca post sperm and oocyte contact.
- increases metabolic rate of zygote
- depolarizes membrane so it is not fertilized by multiple sperm
blastula
hollow ball of cells with a fluid filled inner cavity –> blastocoel
trophoblast cells
(blastula) give rise to chorion and later placenta
inner cell mass
(blastula) gives rise to organism
chorion
extra embryonic membrane that contains chorionic villi
chorionic villi
fingerlike projections that penetrate endometrium, support maternal-fetal gas exchange (future placenta)
umbilical vein
carries oxygenated and nutrient rich blood from placenta to embryo (precedes reaching embryo heart)
umbilical artery
carries deoxygenated blood and waste to placenta
yolk sac
site of early blood development. Support early embryo
amnion
thin, tough membrane filled w amniotic fluid. Shock absorber
gastrulation
generation of 3 layer cell.
deuterostomes
blastopore develops into anus
neurolation
mesodermal cells form a rod –> notochord. Induces a group of ectodermal cells to slide inward creating a neural fold
teratogens
substances that interfere with fetal development –>alcohol, drugs, chemicals
senescence
biological aging
cellular level: failure of cells to divide (shortened telomeres)
organismal level: changes in the body’s ability to respond to changes in the environment
telomerase
reverse transcriptase found in germ, fetal, and tumor cells. Able to synthesize the ends of chromosomes
fetal hemoglobin
has greater affinity for O2, assisting in the transfer of oxygen into the fetal system
foramen ovale
one way valve that connects the right atrium to the left atrium, bypasses lungs
difference between pressure in heart
right side of heart is at higher pressure in fetus
ductus arteriosus
shunts leftover blood from the pulmonary artery to the aorta (bypasses lungs)
ductus venosus
shunts blood returning from the placenta via the umbilical vein directly into inferior vena cava (bypasses liver)
first trimester
major organs developmed
cartilaginous skeleton begins to harden
brain is fairly developed