Placenta (Exam 2) Flashcards
1
Q
The placenta is made up of ______ and _____ tissues, and ______ tissues are never lost.
A
maternal
fetal
fetal
2
Q
Function of the placenta
A
exchange between fetus + mother
prevents mixing of blood
3
Q
The placenta is a(n) (endocrine/exocrine) and _______ producing organ.
A
endocrine
neurotransmitter
4
Q
What two things does the placenta produce which makes it an endocrine organ?
A
progesterone
gonadotropins
5
Q
What gonadotropin does the placenta produce in horses?
A
eCG (equine corionic gonadotropin)
6
Q
What 3 neurotransmitters can the placenta produce?
A
IFN-t (interferon tau)
serotonin (5-HT)
dopamine
7
Q
Which neurotransmitter does the placenta produce in ruminants?
A
IFN-t (interferon tau)
8
Q
Function of IFN-t in ruminants
A
prevents luteolysis (so pregnancy is maintained)
9
Q
What is the significance of the placenta producing serotonin (5-HT) and dopamine?
A
important for fetal brain development
10
Q
The placenta can produce unique proteins or __________ in cattle which has an unknown function.
A
PAG (pregnancy associated glycoproteins)
11
Q
Placentation is the _______ and ______ of the placenta.
A
formation and attachment
12
Q
Term for the early stage of an embryo which will eventually implant into the uterus
A
blastocyst
13
Q
Term for nourishment of embryo from the uterine gland secretions
A
histiotrophe
14
Q
What are the 3 sets of extraembyronic membranes that form during placentation?
A
- yolk sac
- amnion + chorion
- allantois
15
Q
Match each extraembryonic membrane to what its derived from:
- yolk sac
- amnion + chorion
- allantois
A
- splanchnopleure
- somatopleure
- splanchnopleure
16
Q
eCG in mares is also called ______.
A
PMSG (pregnant mare serum gonadotropin)
17
Q
What two things does the splanchnopleure consist of?
A
endoderm + splanchnic mesoderm
18
Q
What two things does somatopleure consist of?
A
ectoderm + somatic mesoderm
19
Q
Splanchnic mesoderm is (avascular/vascular) and somatic mesoderm is (avascular/vascular).
A
vascular
avascular
20
Q
The mature placenta is formed by the fusion of what two extraembryonic membranes?
A
chorion + allantois
21
Q
Fetal blood vessels are provided by the ______ which contracts the endometrium.
A
allantois
22
Q
What is the function of the allantois?
A
exchange of nutrients from maternal blood (in some species)
23
Q
Hemotrophe provides nutrients from _________ while a histiotrophe provides nutrients from _________.
A
maternal blood
uterine glands
24
Q
Two major types of placentae in domestic animals
A
- yolk sac placenta
- chorioallantoic placenta
25
Two other names for "yolk sac placenta" classification
choriovitelline placenta
omphaloid placenta
26
In the yolk sac placenta, the yolk sac fuses with _______.
chorion
27
Which species is the yolk sac placenta common in?
rodents
28
The chorioallantoic placenta divides into 4 sets of classes to categorize the placenta. It classifies them based on what 4 things?
maternal tissue loss
contact areas
number of layers
projections
29
What are the 2 classes of chorioallantoic placenta based on maternal tissue loss?
1. non-deciduate
2. deciduate
30
What is meant by "non-deciduate" placenta?
no loss of maternal tissue at birth
31
What is meant by "deciduate" placenta?
maternal tissue is lost at birth
32
Which species have a non-deciduate placenta?
pig, horse (typical in ungulates)
33
Which species have a deciduate placenta?
carnivores
34
What is unique about ruminants in terms of the class of placenta based on maternal tissue loss?
they are partially deciduous
35
What are the 3 classes of chorioallantoic placenta based on contact area?
1. diffuse
2. cotyledonary
3. zonary
36
Term for smooth region of placenta that is not modified for exchange with the mother
chorion laeve
37
Term for modified region in placenta for exchange of gas, nutrients, and waste with the mother
chorion frondosum
38
How is the chorion frondosum modified for exchange between mother and fetus?
increased surface area (branching, villi, or folds)
39
The diffuse placenta is made entirely of _________.
chorion frondosum
40
What 3 species have a diffuse placenta?
horse
pig
camel
41
In the cotyledonary placenta, the fetal ______ pairs with the uterine ______ to form _______.
cotyledon
caruncle
placentome
42
Which species has a cotyledonary placenta?
ruminants
43
The zonary placenta has a belt or band of _________.
chorion frondosum
44
Which species have a zonary placenta?
carnivores (dogs/cats)
45
Name the 3 fetal layers of the placenta
1. fetal endothelium
2. fetal connective tissue
3. fetal epithelium
46
Fetal connective tissue is derived from _______ ______ of the chorion and ______ _______of the allantois.
somatic mesoderm
splanchnic mesoderm
47
The fetal epithelium layer of the placenta can also be called ________.
trophoblast cells (or cytotrophoblast cells)
48
What are the 3 maternal/uterine layers of the placenta?
1. maternal epithelium
2. maternal connective tissue
3. maternal endothelium
49
The fetal and maternal endothelium layers line ________.
blood vessels
50
What are the 4 different classes of the chorioallantoic placenta based on layers?
1. epitheliochorial
2. synepitheliochorial
3. endotheliochorial
4. hemochorial
51
The epitheliochorial placenta has __ total layers and __ maternal layers are lost.
6
0
52
Which species have the epitheliochorial placenta?
horse
pig
partial ruminant (select regions)
53
The synepitheliochorial placenta has __ layers. Why?
5
fetal + maternal epithelium fuse
54
Which species have a synepitheliochorial placenta?
ruminants (select regions)
55
The hemochorial placenta has __ layers between fetus and mother. Which layers are lost?
3
all 3 maternal layers
56
Which 2 species have a hemochorial placenta?
primates
rodents
57
In the endotheliochorial placenta, __ layers separate the fetus from the mother. Which layers are lost?
4
lose maternal epithelium & maternal connective tissue
58
Which species have a endotheliochorial placenta?
carnivores (dogs/cats)
59
What are the 3 classes of chorioallantoic placenta by its projections?
1. folded
2. villous
3. labyrinthine
60
In the folded chorioallantoic placenta, the macroscopic folds are called ______ and the microscopic folds are called ______.
plicae
rugae
61
Which species has a folded chorioallantoic placenta?
pig
62
In the villous chorioallantoic placenta, the ____ fetal insert into the ____ crypts.
fetal
uterine
63
Which 2 species have a villous chorioallantoic placenta?
horse
ruminants
64
The labyrinthine class of chorioallantoic placenta forms complex network where any connective tissue seen is of the _____.
fetus (fetal CT)
65
Which species have a labyrinthine chorioallantoic placenta?
carnivores (dog/cat)
66
(T/F) The porcine placenta is highly invasive and has diffuse placentation.
False - least invasive
67
Match the porcine placenta to its appropriate classes based on:
1. maternal tissue loss
2. contact areas
3. layers
4. projections
1. non-deciduate
2. diffuse
3. epitheliochorial (6 layers)
4. folded
68
Porcine gestation length
114 days
69
Porcine placenta attachment begins ____ to ____ days after ovulation.
12-13
70
In the porcine and equine placenta, glandular secretions accumulate in ________.
areolae (areolar region)
71
What is unique about the RBCs on the fetal side of the porcine placenta?
nucleated (immature)
72
Except for the _______, how does all fetal connective tissue appear?
horse
pale, mesenchyme-like
73
Match the equine placenta to its appropriate classes based on:
1. maternal tissue loss
2. contact areas
3. layers
4. projections
1. non-deciduate
2. diffuse
3. epitheliochorial
4. villous
74
In the equine placenta, fetal and uterine tissues interact at ___________.
microcotyledons (microplacentomes or microcaruncles)
75
Per microcotyledon in the equine placenta, there is/are __ areolae per area.
1
76
What specialized fetal epithelial cells break off and implant into uterine tissue in the equine placenta?
endometrial cup cells
77
Function of endometrial cup cells (equine placenta)
produce eCG (equine choriogonadotropin) to increase progesterone via accessory cells
78
What is the concern with endometrial cup cells in the equine placenta?
maternal immune system starts attacking them so they are only function until 120 days of gestation
79
What is significant about implantation of the embryo in the equine placenta?
embryo but "roll" between and contact both uterine horns to recognize pregnancy
80
Term for calcified materials floating in the allantoic fluid which is common in equine pregnancies
hippomanes
81
Equine gestation length
340 days
82
Equine placenta attachment occurs ___ to ___ days after ovulation.
35-40
83
Match the ruminant placenta to its appropriate classes based on:
(Note differences in cow vs. ewe/doe in layers)
1. maternal tissue loss
2. contact areas
3. layers
4. projections
1. non-deciduate to partially deciduate
2. cotyledonary
3. cow: epitheliochorial, ewe/doe: synepitheliochorial
4. villous
84
Cow gestation length
9 months (280 days)
85
Cow placenta attachment occurs ___ to ___ days after ovulation.
28-32
86
Ewe + goat gestation length
150 days
87
The ewe and goat placenta attaches ___ to ___ days after ovulation.
14-16
88
What 4 cell types can be seen in the ruminant placenta?
1. binucleate
2. trinucleate
3. trophoblast giant cells
4. cryptal giant cells
89
The placentomes of the cow have a _____ shape while the ewe and goat are _____.
convex
concave
90
What is unique about the placentomes in the ewe and goat?
presence of melanocytes (dark color)
91
Match the carnivore placenta to its appropriate classes based on:
1. maternal tissue loss
2. contact areas
3. layers
4. projections
1. deciduate
2. zonary
3. endotheliochorial
4. labyrinthine
92
Gestation length of dog and cat
63 days
93
The queen's placenta attaches ___ to ___ days after ovulation.
11-12
94
The bitch's placenta attaches ___ to ___ days after ovulation.
14-17
95
Dog and cat pregnancy can be terminated with a _______ injection, but is not recommended due to serous side effects.
estrogen
96
List the 5 layers of the carnivore placenta
1. chorioallantois
2. labyrinth
3. spongy layer
4. supraglandular layer
5. deep glandular layer
97
In the labyrinth layer of the carnivore placenta, the chorionic villi branch and fuse extensively forming _______.
lamellae
98
Which species has obvious, regular layers of lamellae? Which has irregular and complex lamellae?
cat
dog
99
Lamellae of the carnivore placenta have a ________ core and made up of what 3 cell types?
fetal connective tissue
cytotrophoblasts
syntrophoblasts
decidual cells
100
Which cell type in the lamellae of the carnivore placenta erode the uterine epithelium and lamina propria to forma endotheliochorial placenta?
syntrophoblasts
101
________ are cells that form one large multinucleated mass of cytoplasm in the carnivore placenta.
syntrophoblasts
102
Which cells in the carnivore placenta are located at the base of the lamellae toward the uterus? Which species are they more prominent in?
decidual cells
cat
103
What is the possible function of decidual cells?
prevent rejection of placenta (inhibit T cell response)
104
The spongy layer of the carnivore placenta is made of distended _______.
uterine glands
105
Which layer does separation of the carnivore placenta occur at parturition?
spongy layer
106
________ layer is only prominent in the dog and _______ layer is more prominent in the dog.
supraglandular
deep glandular
107
What is a source of iron for the developing carnivore fetus?
marginal hematomas
