pregnancy Flashcards
(159 cards)
1
Q
wdwm by gestation period ?
A
the time during which the development of the conceptus occurs
2
Q
when does ovulation takes place ?
A
about two weeks after the LMP - last menstrual period
3
Q
how many weeks does pregnancy take ?
A
40 weeks
4
Q
from fertilization till week 8 wt do we call
A
embryo
5
Q
wt do we call the duration from week 9 to birth ?
A
fetus
6
Q
wt do we call the duration at birth ?
A
infant
7
Q
where are the eggs stored in ?
A
ovaries
8
Q
after the egg is released for how many hours can it live ?
A
12 to 24 hrs
9
Q
when an egg is fertilized by the sperm the egg becomes wt ?
A
a zygote
10
Q
for how long does the sperm survive in the female preproductive tract ?
A
up to a week
11
Q
who connects the ovaries to the uterus ?
A
fallopian tubes
12
Q
when does ovulation takes place ?
A
one or two weeks after ur period ta2reeban
13
Q
wdwm by capicitation
A
makes the sperm move faster to the egg
14
Q
A
15
Q
How can a sperm enter a egg , wt are the conditions
A
1-motility must be enhanced 2- their membranes must become fragile (weak) so that the hydrolytic enzymes in their acrosomes can be released
16
Q
Wt keeps the sperm tough and stable ?
A
Cholesterol
17
Q
How do sperm find their way to a released oocyte in the uterine tube ?
A
Sperm have receptors that sense the direction of fluid flow , temp and certain chemicals
18
Q
Sperm use wt type of receptors protein to the egg ?
A
Olfactory proteins to sniff the chemical released by the oocyte and its surrounding cells
19
Q
Wt are the two barriers a sperm must reach ?
A
1- corona radiata 2- deeper zona
20
Q
for wt is the acrosomal enzymes used ?
A
to get through zona pellucidaa
21
Q
wdwm by penetrate ?
A
enter or break through stuff
22
Q
At least two mechanisms help ensure monospermy:
A
the oocyte membrane block
and the cortical reaction.
23
Q
wt happens when the sperm and egg membranes fuse ?
A
calcium ions are released from the eggs endoplasmic reticulum which trigers cortical reaction
24
Q
wdwm by cortical reaction
A
where enzymes prevent other sperm from entering the egg ensuring only one sperm fertilizes it
25
26
Wdwm by zona reaction ?
Is a process that occurs after a sperm fertilizes an egg . It involves changes in the zona pellucida to prevent polyspermy
27
Wt happens when the sperms cytoplasmic enter the oocyte ?
- it looses its plasma membrane
28
Explain wt happens in comlpetion of meiosis || and fertalization
after the sperm enters the oocyte , it loose its plasma mambrane and the nucleus expands forming male pronucleus . The egg was paused in meiosis 2 when the sperm enters calcium signals wake it up, and it finishes meiosis II, forming the female pronucleus and a tiny extra cell called the second polar body (which later disappears).
4. DNA Preparation: Now, both the male and female pronuclei copy their DNA while moving toward each other.
5. Fertilization Happens: Once the pronuclei meet, their membranes break, and their DNA mixes, forming a zygote (the first cell of the baby).
29
How many is morula ?
3 days
30
How many days is the 4 cell stage ?
2 days
31
How many days is the early blastocyst ?
4 days
32
How many days is the implanting blastocyst ?
7 days
33
Wt do we have inside the blastocyst?
Trophoblast , blastocyst and embryoblast
34
Which one is the outer layer of blastocyst ?
Trophoblast
35
Wdwm by cleavage ?
The zygote divides into smaller cells but the cell dont grow larger
36
Wt happens by day 4 or 5 after fertilization
Zona pellucida starts to break down and is called now blastocyst
37
The trophoblast has several key roles during development
Improtant role in kpimllanting the embryo in the wall of the uterus 2-major role in chorion 3- it protects the conceptus from attack by the mothers immune cells
38
chorion contirbutes in the formation of ?
Placenta
39
Wts a placenta
The organ that allows the exchange of nutrients bw mother and the embryo
40
When does thee blastocyst adheres to uterine wall ?
Day 6 after fertilization
41
Wt happens in day 7 after fertilization ?
Implantation begins as trophoblast invades uterine wall
42
Wt happens in day 11
Implantation complete ! Aminiotic sac and yolk sac form
43
For how many days does the blastocyst travels in the uterine cavity ?
Two too three days
44
wt happens six to seven days after ovulation ?
implantation begins
45
wdwm by windown of implantation ?
a specific time when the lining of the uterus ( endometrium ) is ready for the fertilized egg ( blastocyst to attach and start growing
46
how can a uterus be ready ?
certain hormones ( estrogen and proesterone ) must be high at levels , when these hormones are high the endometrial cells become able to help the blastocyst stick to the uterus
47
when the blastocyst attaches to the uterus , it causes the uterus to respond like a response wt happens ?
1- blood vessels in the uterus become leaky
2- immune cells come into the area
48
wt are the two types of trophoblast ?
1- cytotrophoblast - forms the innermost layer of cells
2- syncytiotrophoblast - forms the outermost layer
49
syncytio how does it help in implantation ?
helps the blastocyst burrow into the uterine
50
implantation takes how many days ?
5 days
51
how is menstruation and corpus luteum related ?
menstruation occurs beacuse corpus luteum degenerates and stop releasing progesterone and estrogens
52
How does the embryo rescue the corpus luteum?
Its syncytiotrophoblast secretes human chorionic gonadotropin (hCG)
53
wt does the hcg do to the uterus lining ?
makes sure the uterus lining is thick and is not shed
54
if the corpus luteum stops producing these hormones wt will happen ?
causes menestruation
55
wt are the two important roles of HCG ?
1- rescuing the corpus luteum
2- prevents the mothers immune system from rejecting the implanted embryo
56
hCG is usually detectable
in the mother’s blood when ?
two days after implantation
57
wt happens to the trophoblast when it enters the endo ?
divides into two types
58
corpus luteum will stay till which month and wt will happen after ?
till second month (8weeks ) , the placenta will then take over producing estro and pro
59
does the maternal blood and fetals blood mix ?
no NEVER
60
who provides nutrients and everything to the embryo ?
at the early stage , the embryo feeds on endometrial cells but by the second month , the placenta provides nutrients oxygen
61
wt is the shape of placenta ?
pancake shaped
62
wts a extraembryonic mesoderm
lines the inner surface of the trophoblast so bw the trophoblast and the embryo . This layer helps in forming structures like the placenta that support the developing embry
63
extraembryonic mesoderm becomes wt by the time
chorion
64
wts a chorion ?
a protective member around the embryo that helps form the placenta
65
wt happens in Implanting 8-day blastocyst.
1- synciotr
erodes the endometrium
2-embryonic disc is separated from the aminion by a fluid
66
wt happens in 12 day blastocyst ?
1- implantation is complete
2- extraembryonic mesoderm is forming a layer beneath the cyto
67
in 12 day blastocyst the ectraembryonic mesoderm wt does it do ?
helps in forming chorion
68
wt happens in 16 day embryo ?
1- trophoblast and associated mesoderm have become the chorion
2-chroionic villi are forming
3- the embryo exhibits all three germ layer , yolk sac and an allantois
69
wt is allantois involved in ?
waste removal and blood vessels development for plcenta
70
wt are the thee primary germ layers ?
1- ectoderm
2- mesoderm
3- endoderm
71
decidua capsularis , decidua basalis , aminion and yolk sac are formed by which week ?
4 1/2 week
72
wt does the umbilical vessels do in 4 1/2 week ?
they carry oxygen from placenta to the embryo and waste products from the embryo to the placenta
73
how is chorioninc villi and placenta related ?
chroionic villi grow into the uterine wall they touch to the mothers blood allowing nutrients , oxygen to pass from the maternal blood to the body , as the villi grow and get more complex they form placenta
74
where does the blood vessels form ?
chorionic villi which turns into umbilical arteries and vein
75
The part of the endometrium under the embryo is called
decidua basalis
76
the part around the embryo is called
decidua capsularis
77
Together, decidua capsularis and decidua basalis make up wt ?
they make up the placenta
78
The placenta is usually fully functional by which month ?
by the end of the third month of pregnancy
79
wt is the primry role of HCG ?
mintain the corpus lutem in the ovary , which continues to produce proesterone
80
proesterone is important for wt ?
maintaining the uterine lining and prevents mesntruation
81
as implantation happens , the blastocyst begins changing into wt ?
gastrula
82
the embryoblast divides into two layers
epiblast and hypoblast
83
why is epiblast important ?
this layer is the source of the embryo itself
84
why is hypoblast important ?
forms part of the yolk sac and contirbutes to the formation of the other structures
85
epiblast and hypoblast together they make uo wt ?
embryonic disc
86
from epiblast wt will emerge ?
three primary germ layers
87
wt are the primary germ layers
ectoderm , mesoderm and endoderm
88
ectoderm forms wt ?
forms the skin and nervous sys
89
mesoderm forms wt ?
muscles and bones and cardiovascular sys
90
endoderm forms wt ?
internal struc like lungs and digestive sys
91
wdym by extraembryonic membrane ?
membranes that surround the embryo and are key to its survival and growth
92
which extraembryonic membrane is the first to form ?
amnion
93
amnion arises from which cell ?
epiblast
94
amnion contains wt ?
amniotic cavity which is filled with amniotic fluid
95
amniotic fluid has several functions
1- protects the embryo from physical trauma
2-maintains a stable temp around the embryo
3- prevents the embryo rapidly growing parts from sticking together
4- allows the embryo to move freely
96
The primitive gut ?
early form of the digestive tract in an embryo
97
yolk sac forms from wt ?
primitive gut
98
roles of yolk sac
1- It contributes to the formation of part of the digestive system
2- source of the first blood cells.
3-It is where the primordial germ cells (early versions of sperm and eggs) develop before migrating to the gonads (testes or ovaries) to form mature reproductive cells later on.
99
wt is an allantois and wt does it do ?
a small outpocketing of the embryonic tissue located near the caudal (tail) end of the yolk sac.
1-It forms the structural base for the umbilical cord, which connects the embryo to the placenta.
2-Over time, the allantois becomes part of the urinary bladder.
100
Chorion
the outermost extraembryonic membrane,
101
function of chorion
helps the placenta
102
plays a key role chorion in wt ?
supporting nutrient and gas exchange between the mother and the fetus
103
umbilical cord
connects the developing fetus to the placenta The cord contains umbilical arteries and a vein that carry blood between the embryo (and later the fetus) and the placenta.
104
Gastrulation is a critical phase of embryonic development that takes place during which week ?
week 3
105
gastrulation begins with the formation of wt ?
primitive streak
106
the first layee that will eventually form structures like wt ?
digestive system , respiratory system and urinary system
107
which one is the innermost layer ?
endoderm
108
which one is the middle layer ?
mesoderm
109
mesoderm gives a rise to a wide range of structures like wt ?
muscles , bones , circulatory system and kidneys
110
how is notochord formed ?
as the mesoderm forms , a group of mesodermal cells underneath the primitive streak aggregate to form the notochord
111
notochord is important for wt ?
proper development of the nervous system and spine
112
how is ectoderm formed ?
the cells that remain on the surface of the embryo form the ectoderm the OUTERMOST LAYER
113
ectoderm will give rise to wt ?
nervous system including the brain and spinal cord and skin epidermis
114
after gastrulation wt phase do we have ?
organogenesis
115
wdwm by organogenesis ?
the process of organs and organ system begining to form
116
by the end of the embryonic period ( 8 weeks ) all organ system are wt ?
recognizable but not fully developed
117
At the beginning of organogenesis wt happens ?
the embryo folds
118
wt happens in lateral folding ?
1- endoderm folds and forms a tube called primitive gut , this primitive gut becomes the lining of ur digestive system and respiratory
119
which gut also helps in the formation of lungs and airways ?
primitive
120
wt happens in Neurulation ?
1- a signal from the notovhord makes the ectoderm thick and forms a neural plate which is the begining of ur brain and spinal cord
2-neural plate folds inward forming neural grrove
3- the folds come together to form a neural tube this tube will turn into ur brain and spinal
121
the anterior part of the neural tube will become wt ?
bran
122
the posterior part of the neural tube will become wt ?
spinal cord
123
Neural Crest Cells
These cells are special ectodermal cells that migrate away from the neural tube during development.
124
roles of Neural Crest Cells:
1-Cranial, spinal, and sympathetic ganglia (groups of nerve cells).
Adrenal medulla (part of the adrenal glands).
Pigment cells of the skin (melanocytes).
Some connective tissues.
125
By the end of the first month of development wt happens ?
the three primary brain vesicles (forebrain, midbrain, hindbrain) are visible
126
By the end of the second month wt happens ?
the brain's basic structures are recognizable, and brain waves can be recorded.
127
The notochord helps in
organizing the body
128
notochord will be replaced wth wt >?
he vertebral column (the spine
129
the largest mesodermal structures are
somites
130
somites give rise to ?
Sclerotome: Forms the vertebrae (spine) and ribs.
Dermatome: Forms the dermis (inner layer of skin) in the dorsal (back) region.
Myotome: Forms the skeletal muscles of the neck, trunk, and limbs.
131
Intermediate Mesoderm: forms ?
gonads (reproductive organs) and kidneys.
132
Somatic Mesoderm
orms the dermis of the ventral body region (front of the body), the parietal serosa (lining of body cavities), and most of the tissues of the limbs.
133
Splanchnic Mesoderm:
Forms the heart, blood vessels, connective tissues, and the walls of digestive and respiratory organs.
134
who becomes the future vertebral column
notochord
135
specific period when the uterine lining is most receptive to the blastocyst
window of implantation
136
why does the trophoblast secretes digestive enzymes when it adhered the endometrium
helps break down the uterine tissue and allow blastocyst to burrow into endo lining
137
degeneration of corpus luteum and progestrons not released causes wt ?
menstruation
138
wt does the syncy produces and why ?
HCG to rescue the corpus luteum it goes to the uterus and tell it ' hey keep the uterus lining thick "
139
The corpus luteum stays active for about ?
2 month s
140
chorionic villi lies where
maternal blood
141
maternal blood is found where ? wt do we call the spaces ?
intervillous spaces
142
placenta is fully functional by the end of which month
3
143
yolk sac forms from cells called ?
from cells of the primitive gut
144
who forms ubilical cord ?
allantois
145
is a groove that appears on the surface of the embryo (on the epiblast layer
primitive streak
146
who marks the posterior and infoeriot part of the body ?
primitive streak
147
It is the starting point for the development of the nervous system, the spinal cord, and the brain.
primitive streak
148
is a tube-like structure that forms from the endoderm (the innermost germ layer) during early development.
primitive gut
149
neural groove forms by folding wt ?
neural plate
150
when the neural plate deepens it becomes wt ?
neural groove
151
wt are the three mesodermal that agregrates on each side of the notochord ?
somite
intermediate mesoderm
lateral plate mesoderm
152
somites divide into three parts
dermatomes , myotomes and sclerotomes
153
which mesoderm forms the kidneys and gonads ?
intermediate mesoderm
154
which somite forms the dermis (dorsal ) ?
dermatomes
155
which somite forms the skeletal muscles ?
myotomes
156
sclerotomes forms wt ?
vertebrae and ribs
157
lateral plate mesoderm( somatic forms wt ?
limb bud
smooth muscle of gut
visceral serosa
parietal serosa
dermis ( ventral )
158
splanchnic mesoderm makes ?
heart , blood vessels and most CT
159
who forms the serosae of the coelom ?
two types of later plate mesoderm cooperate
