conception and fetal development Flashcards
mitosis produces _____ cells
diploid
mitosis makes ___ and ____ possible
growth
development
______ produces exact copies of original cell
mitosis
____ occurs before conception
meiosis
during meiosis, ____ cells in testes and ovaries give rise to gametes
diploid
the result of meiosis is a ______ number
haploid
a haploid number is half of the amount in _____
mitosis
______ (meiosis/mitosis) produces reproductive cells
meiosis
____ is the process by which female gametes are produced
oogenesis
all ______ that females will produce in her lifetime are present at birth
ova
ovary produces ____ cells before birth
oogonial
the ___ is the female gamete
ovum
an ____ undergoes meiotosis to form an ovum
oocoyte
during oogenesis, the oocyte goes through its first meiotic division at _______
puberty
at ________ the second meiotic division occurs
ovulation
during the second meiotic division of oogenesis, a _____ _____ is produced
mature ovum
_____ _____ in seminiferous tubules produce gamete
germinal epithelium
germinal epithelium in ______ ______ produce gamete
seminiferous tubules
during the first meiotic division in the production of sperm, _________ replicates
spermatogonium
during the second meiotic divison in the production of sperm, 4 ______ are formed
spermatids
the top of the head of a sperm is the _______
acrosome
the rest of the head of a sperm is ______
nucleus
the nucleus of a sperm contains all the _______ _______
genetic material
the middle of a sperm has a ______ for energy
mitochondria
the tail of a sperm has ______ for motility
flagellum
fertilization is the process by which a sperm fuses with an ovum to form a new _____ cell or ______
diploid
zygote
the process of fertilization takes place in the _______ of the fallopian tube
ampulla
the process of fertilization takes place in the ampulla of the ______ _____
fallopian tube
high levels of estrogen during ovulation cause _____ within the fallopian tubes, which helps the ovum
peristalsis
high levels of estrogen during ovulation cause thinning of _____ ______, which helps the sperm
cervical mucus
lack of ______ can be the cause of ectopic pregnancies
estrogen
sperm can survive in the female reproductive tract for ___-____ hours but are only believed healthy for about ____ hours
48-72
24
ova is considered fertile for about ___-____ hours after ovulation
12-24
sex of the ______ is determined at fertilization
zygote
2 phases of development after fertilization:
cellular _____
cellular _______
multiplication
differentiation
the zygote begins cellular multiplication while still in the ______ _______
fallopian tube
____ helps the zygote with cellular multiplication
estrogen
during the process of fertilization, there are 2 cells after _____ hours
36
in the process of fertilization, there are 4 cells after _____ hours
48
during fertilization, implantation occurs on days _____-_____
7-10
ideally implantation occurs on the ______ side of the ______
posterior
fundus
the posterior side of the fundus is ideal for implantation bc there’s increased ______ _____
blood supply
the posterior side of the fundus is ideal for implantation bc the _____ is thick
endometrium
the posterior side of the fundus is ideal for implantation bc it ______ _____ ____ after birth
limits blood loss
______ makes the fundus ideal for the egg
progesterone
the ______ period are the first 2 weeks after conception
pre embryonic
the ____ stage is when the fertilized egg is trying to implant
pre embryonic
the _____ period is the 3rd to 8th week of development
embryonic
the _____ period is 9 weeks to birth
fetal
the pre embryonic period is the first ______ weeks after conception
2
the embryonic period is the _____-______ week of development
3rd-8th
the fetal period is week ___ to ______
9-birth
in the pre embryonic period, the first cell division is the ______
zygote
in the pre embryonic period, cleavage cell division forms a ______
morula
the inner cell mass of a morula are called ________
blastocysts
blastocysts form _____ and _______
embryo
amnion
in the pre embryonic period, the outer layer of cells are called _______
trophoblasts
______ are the outer layer of blastocysts
trophoblasts
_____ occur on the 4th day after fertilization
blastocysts
trophoblasts form the _____ and ______
placenta
chorion
in the embryonic period, the embryo is vulnerable to _____
teratogens
development in the embryonic period is ________ and ________
cephalocaudal
peripheral
cephalocaudal means higher amounts of oxygen are delivered to the _____ and ____ than to the extremities
brain
heart
at what stage of fetal development does implantation take place?
a. embryo
b. morula
c. blastocyst
d. zygote
blastocyst
after implantation the endometrium is called ______
decidua
maternal part of the placenta develops from the _____ ______
decidua basalis
at about the 10th to 14th day, blastocyst cells differentiate into primary germ layers called the _______, _______, and ________
ectoderm
mesoderm
endoderm
the ____ forms the CNS, special senses, skin and glands
ectoderm
the ________ forms skeletal, urinary, circulatory, and reproductive organs
mesoderm
the ______ forms the respiratory system, liver, pancreas, and digestive system
endoderm
the umbilical cord carries ___ _____ and _____
blood flow
nutrients
the umbilical cord has 2 _____ and 1 _____
arteries
vein
the 2 umbilical arteries carry _____ and ________ blood away from the fetus
waste
deoxygenated
the umbilical vein carries _______ blood from the _____ to the ______
oxygenated
placenta
fetus
_____ _____ is a thick gelatinous substance that surrounds and cushions the veins
Whartons jelly
as the placenta develops, the umbilical cord is also being formed from ______
amnion
development of umbilical cord:
_____ ____ attaches embryo to yolk sak
body stalk
development of umbilical cord:
body stalk contains blood vessels that extend into ______ _____
chorionic villi
development of umbilical cord:
stalk fuses with embryonic portion of placenta to provide _____ pathway from chorionic villi to embryo
circulatory
development of umbilical cord:
as body stalk elongates to become the umbilical cord, vessels in cord decrease to _____ large vein and _____ smaller arteries
1
2
development of umbilical cord:
_____ ____ prevents compression of cord in utero
Whartons jelly
outer, thicker membrane of umbilical cord is called the ______
chorion
the chorion membrane surrounds _____ _____ and the _____
amniotic fluid
fetus
the ______ is the inner, thinner membrane of the umbilical cord
amnion
there’s approximately ____L or ____mL of amniotic fluid at term
1
1000
amniotic fluid is _______(acidic, alkaline)
alkaline
_____ ______ keeps the fetus warm
amniotic fluid
amniotic fluid helps the fetus maintain a constant ____ _______
body temp
body temp of fetus should be _____F
98.6
amniotic fluid permits symmetric _____ and _____
growth
development
_____ ____ cushions the fetus from trauma
amniotic fluid
amniotic fluid allows the umbilical cord to remain relatively free of _______
compression
amniotic fluid promotes fetal _________
movement
________ is when there is too much amniotic fluid
polyhydramnios
polyhydramnios is more than _____L of amniotic fluid
2
polyhydramnios can be caused by malformations of ____ or ___ ____, and ____ _____
CNS or GI tract
maternal diabetes
_________ is when there is not enough amniotic fluid
oligohydramnios
oligohydramnios is less than ____ cc of amniotic fluid
500
oligohydramnios can be caused by _____ _____ or maternal _______
kidney agenesis
hypertension
fraternal twins are _____ which means there are 2 eggs
dizygotic
identical twins are ______ which means there is 1 egg
monozygotic
fraternal (dizygotic) twins arise out of 2 separate ___ and 2 separate _______
ova
spermatozoa