XII: Chapter 3- Human reproduction Flashcards
How many testicular lobules are present in each testis?
250
How many seminiferous tubules are present in each testicular lobule?
1 to 3
What lines the inside of the seminiferous tubules in humans?
Male germ cells and sertoli cells
Male germ cells in humans are called
Spermatogonia
Name the ducts of reproductive system of human males in order from seminiferous tubules to ejaculatory duct.
Seminiferous tubules -> Rete testis -> vasa efferentia -> epididymis -> vas diferens -> ejaculatory duct
Secretions of which glands help in lubrication of penis?
Bulbourethral gland
What is the length of a human ovary?
2 to 4 cm
Each ovary is covered by a thin epithelium. True/false?
True
Name the female accessory ducts.
Oviducts, uterus and vagina
The uterus is pear shaped. True/false?
False. The uterus is inverted pear shaped.
How is the uterus (in human females) attached to the pelvic wall?
Through ligaments
Name the layers of uterine wall.
Outer perimetrium
Middle myometrium
Inner endometrium
The cushion of fatty tissue covered by skin and pubic hair in the reproductive system of human females is called
Mons pubis
What are the fleshy folds which extend down from mons pubis and surround the vagina called?
Labia majora
How many mammary lobes are present in each mammary gland?
15-20
The alveoli of mammary glands open into
Mammary tubules
Mammary duct in mammary gland is formed by
All the mammary tubules of each lobe
What do the mammary ducts of mammary gland join and form?
Mammary ampulla
Secondary spermatocytes in males undergo equational division to form
Spermatids
What is the process of transformation of spermatids to spermatozoa called?
Spermiogenesis
What is spermiation?
It is the process of release of spermatozoa from the seminiferous tubule.
Luteinising hormone in males acts on which cells? What are these cells stimulated to do?
LH acts on Leydig cells and stimulates synthesis and secretion of androgens.
Which process do the androgens in male regulate?
Spermatogenesis
FSH in males acts on which cells? What are these cells stimulated to do?
FSH acts on sertoli cells and stimulates the secretion of factors which help in spermiogenesis
How many sperms are produced by human males during coitus?
200 to 300 million sperms
For normal fertility, what percentage of total sperms released by males during coitus must have normal shape and size?
60%
For normal fertility, what percentage of total sperms released by males during coitus must show vigorous motility?
40%
Secretions of which ducts are important for maturation and motility of sperms in humans?
Epididymis, vas deferens, seminal vesicles, and prostrate
How many oogonia are formed in each fetal ovary?
Couple of million
At which stage are the primary oocyte (in human females) arrested?
Diplotene stage of Prophase I
How many primary follicles are left in each ovary at birth?
60,000- 80,000
Which oocyte does a secondary follicle have?
Primary oocyte
Antrum is present in which follicle in a human female?
Tertiary follicle
Inside which follicle does the primary oocyte in females complete its first meiotic division?
tertiary follicle
How many blastomeres does the morula have?
8 to 16
WHat forms chorionic villi?
Trophoblast layer of blastocyst
The levels of cortisol and thyroxine are high during preganancy. True/false?
True
Foetus develops forelimbs by which month of pregnancy?
Second month
By which month of pregnancy do the eyelids separate?
6th month
By which month of pregnancy is the body covered with fine hair?
6th month
What is nidation?
Implantation (of blastocyst)
In which month of pregnancy do the testis of foetus descend into scrotum?
7th month
Where are testis formed in humans?
Abdominal cavity
How do the testis descend from abdominal cavity into scrotum?
Through inguinal canal
What connects the lower end of testis to scrotal wall?
Gubernaculum
Are both testis in males present on the same level?
No, left testis is lower than right testis.
What carries blood vessels, nerves, lymphatics and vas deferens inside inguinal canal?
Spermatic cord
Name the muscle present in scrotum?
Dartos and cremaster muscle
How do the dartos and cremaster muscles maintain the temperature of scrotum in winter?
Dartos- contracts and causes wrinkling of scrotal skin
Cremaster- Contracts and pulls scrotum towards abdomen
Where is testis located in elephants?
Inside abdominal cavity
Where is testis located in whales?
Inside abdominal cavity
What is the outermost double layer peritonium called in testis?
Tunica vaginalis
What is the white fibrous connective tissue surrounding the testis called?
Tunica albuginea
Testicular septa are formed by
Invaginations of tunica albuginea
What is the innermost, highly vascular layer that surrounds the testicular lobules in testis called?
Testicular vasculosa
What is the straight part of seminiferous tubules called?
Tubuli recti
The structure formed by the fusion of tubuli recti is called
Rete testis
How many vasa efferentia are present in a testis?
12-15
Where do sperms mature?
Cauda epididymis
Intra-testicular duct system in humans includes?
Tubuli recti
Rete testis
Vasa efferentia
What is the failure of descent of testis into scrotum called?
Cryptorchidism
Monorchidism is observed in which animal?
Ascaris
Which is the most coiled part of epididymis?
Caput epididymis
How long does the epididymis store sperms?
from one to two weeks upto one months
What is the function of stereocilia in epididymis?
Absorption of fluid in caput
What does the epididymis in humans develop from?
Mesonephric/wolffian duct
What does the seminal vesicle in humans develop from?
Mesonephric/wolffian duct
Fibrinogen is present in which male reproductive gland’s secretions?
Seminal vesicles
Can semen clot?
Yes
Are citrate ions present in semen?
Yes
Where are cowper’s glands located?
In the membranous urethra
Where do the cowper’s glands open?
In the penile urethra
Pre-ejaculatory fluid in males is formed by
Cowper’s glands
Which glands are present on the prepuce of the penis?
Tyson’s glands
What is the function of tyson’s glands?
Lubricated glans penis with their secretions
What is the secretion of tyson’s gland called?
Smegma
What signals the erection of penis?
Nitric oxide
Which somatic nervous system controls the erection of penis?
Parasympathetic nervous system
Which somatic nervous system controls ejaculation?
Sympathetic nervous system
What percent of secretions in semen are of prostate gland?
20-30%
What is the quantity of semen ejected per intercourse?
2-3 ml
Male germ cells in testis are formed from
Mesoderm of yolk sac
WHen do the male germ cells migrate into gonads in humans?
5th week of pregnancy
When do the gonads differentiate into testis and ovary in foetus?
8th week of pregnancy
Sustentacular cells in testis are also called
Sertoli cells
What type of epithelium is germinal epithelium of seminiferous tubules?
Columnar epithelium
Which cells phagocitise dead sperms?
Sertoli cells
What protects the sperms from body’s immune system?
Sertoli cell barrier (blood testis barrier)
Which hormones are secreted by sertoli cells?
Androgen binding protein
Inhibin
Mullerian inhibitory/ anti mullerian hormone
Which hormone concentrates testosterone in seminiferous tubules?
Androgen binding protein
What is the function of inhibin secreted by sertoli cells?
Inhibits FSH
What is the function of mullerian inhibitory hormone?
It inhibits mullerian duct in embryonic life
When does the luminal part of seminiferous tubule form?
At puberty
What are the phases of spermatogenesis?
Multiplication phase
Growth phase
Maturation phase
Spermiogenesis
What happens in the multiplication phase of spermatogenesis?
Mitosis of spermatogonia
What happens in the maturation phase of spermatogenesis?
Meiosis of primary spermatocytes leading to the formation of spermatids
How many days does it take on average to form mature sperms?
74 days
Are sperms of all animals flagellated?
Yes (exception- Ascaris)
Which is the smallest part of a sperm?
Neck
Which part of sperm contains sperm lysins?
Acrosome
What type of sperm lysin is present in sperms?
Hyaluronidase
What is the difference between the proteins found in normal human cell when compared to sperm?
Sperm has no histone proteins but other cells do.
How many centrioles are present in a sperm?
2
What is the function of proximal centriole in sperms?
Role in first cleavage
What is the function of distal centriole in sperms?
Forms basal body for axoneme
How many mitochondria are present in sperms?
20-25
How are mitochondria arranged in a sperm?
They are spirally arranged around axoneme
What is the arrangement of microtubules found in flagella of sperms?
9+2
WHat is the sheath of middle piece of sperm called?
Manchette
What is andropause?
Reduced secretion of testosterone in aging males (50+)
What is aspermia?
Semen is not produced
What is azospermia?
Semen does not contain sperms
What is oligospermia?
Sperm count below 15-20 million sperm per milliliter (mL)
What is inguinal hermia?
Passage of dislocated intestine though inguinal canal
Name the female reproductive glands?
Mammary glands, bartholian gland, skene gland
What attaches ovary to uterus?
Ovarian ligament
What attaches ovary to body wall?
Mesovarium
What kind of tissue is the stroma of ovary?
Fibrous connective tissue
IN which portion of stroma of ovary are the different follicles present?
Cortex
What are salpinges?
Fallopian tube
Which is the widest and longest part of fallopian tube?
Ampulla
Which is the smallest part of fallopian tube?
Interstitium/intramural part
What is the length of fallopian tube?
10-12 cm
What is the fallopian tube called in non mammalian vertebrates?
Oviduct
What are the non ciliated cells present in fallopian tube called?
Peg cells
What is the function of peg cells of fallopian tube?
Secrete tubular fluid to nourish sperms/eggs/zygote
Is the uterus situated in front of the rectum or behind?
Behind
Is the uterus situated in front of the urinary bladder or behind?
Front
How is the uterus positioned in humans?
Anteverted
Do humans have simplex uterus?
Yes
How many sphincters are present in the cervix?
Internal os, external os
Which is the strongest and most powerful sphinctre of the body?
External os of cervix of females
Which muscles are present in the myometrium of uterus?
Circular, longitudinal and oblique
What tissues is the endometrium made of?
Columnar epithelium
What are the two layers of endometrium of uterus?
Stratum basalis
Stratum functionalis
What type of blood vessels are present in stratum basalis of endometrium of uterus?
Straight blood vessels
What type of blood vessels are present in stratum functionalis of endometrium of uterus?
Tortuous blood vessels
How does progesterone change tubular glands of endometrium of uterus?
Makes the corckscrew shaped
What secretes uterine milk in humans?
Corkscrew shaped tubular glands present in stratum functionalis of endometrium of uterus
What nourishes the young embryo prior to implantation in humans?
Uterine milk
Which layer of endometrium sheds during menstruation?
Stratum functionalis
Name the layers of decidua.
Decidua peritalis
Decidua placentalis/basalis
Decidua capsularis
Which layer of decidua has no connection with embryo?
Decidua parietalis
Which layer of decidua contributes to placenta formation?
Decidua placentalis
Which layer of decidua surround embryo from all sides till 26 weeks of pregnancy?
Decidua capsularis
Name the glands present in vagina.
None
Which bacteria form the natural mincroflora of vagina?
Lactobacillus
What are the transverse mucosal fold of vagina called?
Vaginal rugae
How many openings does the vestibule of vagina have?
Urethral and vaginal opening
What forms the prepuce in human females
Anterior tip of labia minora, cover the clitoris
Where is the clitoris present in females?
At the anterior tip of labia minora
What is fourchette?
Fold of skin formed at posterior junction of labia minora
Where are bartholin glands located in females?
One on each side of vaginal orifice
What are the functions of secretions of bartholin glands?
Lubricate vagina, reduce acidity
Which glands are located around urethral opening in females?
Glands of skene
Labia majora in females is homologous to which organ of males?
Scrotum
Labia minora in females is homologous to which organ of males?
Penile urethra
Clitoris in females is homologous to which organ of males?
Penis
Bartholin gland in females is homologous to which organ of males?
Cowper’s glands
Glands of skeme in females is homologous to which organ of males?
Prostrate gland
Mammary glands are modified
sweat glands
Which ligaments suspends mammary glands?
Cooper’s ligaments
What is the function of areolar glands on breasts?
Keep the nipple moist
Areolar glands around areola on mammary glands are modified
Sebaceous glands
Which hormone leads to the development of breasts in human females?
Estrogen
Which hormone stimulates the proliferation of milk alveoli in breasts?
Progesterone
Which hormone is known as the milk let down hormone?
Oxytocin
Which hormone leads to the production of milk during pregnancy?
Human placental lactogen
In which month of pregnancy does oogenesis start?
2nd month
What is the primary oocyte surrounded by in primordial follicle in ovary?
One layer of squamous stromal cells
What is the primary oocyte surrounded by in primary follicle in ovary?
One layer of cuboidal stromal cells
WHat is the primary oocyte surrounded by in secondary follicle in ovary?
Multiple layers of granulosa cell which get surrounded by theca
How many eggs develop into secondary follicles in humans?
450
What is the zona pellucida in tertiary follicle made of ?
Glycoproteins
What secretes the zona pellucida in tertiary follicle?
Secondary oocyte
WHat is the fluid inside antrum in tertiary follicle called
Liquor follicula
What is the theca externa of secondary oocyte made of?
Fibrous layer
Which layer of theca of secondary oocyte has LH receptors?
Theca interna
What is the function of aromatase enzyme on theca interna?
Causes conversion of androgen to estrogen
What divides the granulosa cells of graafian follicle in two clusters of cells? What are these clusters called?
Antrum
1) cumulus oophorus- surrounds the secondary oocyte
2) Membrane granulosa
What is germ hill in graafian follicle?
Granulosa cells which connect secondary oocyte with wall of follicle
What is corona radiata of graafian follicle?
Innermost layer of cumulus oophorous surrounding the zona pellucida
What are released from graafian follicle during ovulation?
Secondary oocyte, zona pellucida and corona radiata
What is the structure left after rupture of graafian follicle and ovulation called?
Corpora haemorrhagicum
What is the difference between corpus albicans and corpus luteum?
Corpus luteum- yellow and glandular
Corpus albicans- white and non glandular
In which stage does the secondary oocyte get arrested?
Metaphase II
What are the different phases of oogensis and what do the entail?
Multiplication phase- formation of primary oocyte from oogonia
Growth phase- primary oocyte arrested
Maturation phase- meiosis I and II of primary oocyte
How long does the multiplication phase of oogenesis last?
5 months
How many primary oocytes turn into secondary oocytes every month?
1
Which cells release androgens in females?
Theca interna cells of secondary oocyte
Which hormones are responsible for the uterine changes in menstruation cycle
Estrogen and progesterone
Which hormones are responsible for the ovarian chagnes in menstrual cycle?
FSH and LH
Can menstrual blood clot?
No.
On which day of menstrual cycle does ovulation occur?
day 14th
On which day of menstrual cycle does the corpus luteum begin to degenerate?
25th day
Around which day of menstrual cycle does estrogen peak occur?
Day 12 to 14
Around which day of menstrual cycle does progesterone peak occur?
Day 21
What are the phases of estrous cycle?
Pro extrous phase
Estrous phase
Metaextrous phase
Diestrous phase
In which phase does ovulation occur in estrous cycle?
Estrous phase
In which phase of estrous cycle is corpus luteum formed?
Meta-estrous phase
In which phase of estrous cycle is progesterone secreted?
Diestrous phase
What is the quiescent stage between two estrous cycles called?
Anestrum
Does bleeding occur in estrous phase?
No
What is the seasonal testicular acitivity in males of some species called?
Rut cycle
What constitutes the egg in animals?
Oocyte+ egg membrane
How many types of egg membrane can an egg (of animals) have?
Primary egg membrane
Secondary egg membrane
Tertiary egg membrane
What secreted the primary egg membrane around the egg in animals?
Oocyte/ovum
What is the primary egg membrane in humans?
Zona pellucida
What is the primary egg membrane of frogs?
Vitelline membrane
What secretes the secondary egg membrane of animal eggs?
Ovary
What is the secondary egg membrane of human eggs called?
Corona radiata
What is the tertiary egg membrane of animal eggs secreted by?
Oviduct/uterus
What is the tertiary egg membrane of frog’s egg called?
Jelly coat
Which type of egg is a human egg on the bases of amount of yolk?
Alecithal
What type eggs do marsupials have on the basis of amount of yolk?
Microlecithal
What type of eggs do amphibians have on the basis of amount of yolk?
Mesolecithal
What type of eggs do reptiles and birds have on the basis of amount of yolk?
Megalecithal
What are isolecithal eggs?
The very little amount of yolk present is uniformly distributed throughout the ooplasm
In what type of eggs is isolecithal condition observed?
Alecithal and microlecithal eggs
What type of eggs do insects have on the basis of amount of yolk?
Megalecithal
What type eggs have heterolecithal distribution of yolk?
Mesolecithal and megalecithal eggs
What type of eggs are found in amphibians on the basis of distribution of yolk?
Telolecithal
What type of eggs are found in reptiles and birds on the basis of distribution of yolk?
Discoidal
What type of eggs are found in prototherians on the basis of amount of yolk?
Megalecithal
What type of eggs are found in prototherians on the basis of distribution of yolk in eggs?
Discoidal
What type of eggs are found in insects on the basis of distribution of yolk in eggs?
Centrolecithal
What are eggs which have shells called?
Cleidoic eggs
Which is the largest cell of human body?
Egg
What is germinal vesicle?
The enlarged nucleus of egg of humans
What do the cortical granules of human egg contain?
Hydrolytic enzymes and mucopolysaccharides
Which is the animal pole of human egg?
Part of egg from where polar body extrudes out
Perivitelline space in egg is present between
Zona pellucida and oocyte
What is the ground substance of corona radiata?
Hyaluronic acid
How long does the human sperm’s viability last?
24 to 48 hours
How long does the human egg’s viability last?
48 to 72 hours
How long does capacitation of sperm take?
6 to 7 hours
How does the destabilization of plasma membrane of sperm take place?
By rearrangement of glycoproteins and dissolution of cholesterol
What is the speed of a hypermotile sperm?
4 to 5 mm/min
What type of movement does the flagella of a hypermotile sperm perform?
Whiplash movement
Which chemical propels sperm towards uterine cavity?
Prostaglandins
Which is the acidic protein present on sperm’s membrane- anti fertilin or fertilin?
Antifertilin
Which is the glycoprotein on egg’s surface- antifertilin or fertilin?
Fertilin
When does acrosome reaction occur?
When sperm binds to ZP3 receptor on zona pellucida
What causes the exocytosis of sperm lysins from acrosome in acrosomal reaction?
Calcium
Which enzymes dissolves hyaluronic acid?
Hyaluronidase enzyme
Which enzyme digests corona radiata of egg?
Corona pentrating enzyme
Which enzyme digests zona pellucida of egg?
Acrosin/ zonalysin
How does fast block to polyspermy occur in egg?
By opening of Na+ channels leading to rapid depolarisation of oolema
What causes the exocytosis of cortical granules from eggs into perivitelline space?
Calcium ions
How thick is the fertilization membrane?
900 Å
What leads to slow block to polyspermy in human egg?
Cortical and zona reaction
Zona reaction happens in human egg due to?
Absorption of water
Which part of sperm enters the the zona pellucida of egg during fertilization?
Whole sperm enters but middle piece and tail degenrates
How does sperm make it possible for meiosis II of secondary oocyte to be completed?
Sperm destroys metaphase promoting factor (MPF) of egg and turns on anaphase promoting factor (APF)
What happens in amphimixis step of syngamy of sperm and egg?
Chromosomal membrane dissolves and chromosome of sperm and egg mix
What is embryology?
Study of first eight weeks of pregnancy after fertilisation
How long does the first cleavage in zygote in humans take?
30 hours
How long does the second cleavage in zygote in humans take after fertilization?
40 hours
What are the phases of interphase in cleavage of zygote in humans?
Only S-phase, G1 and G2 phase are absent
What is nucleocytoplasmic ratio?
It is a ratio of the size of the nucleus of a cell to the size of the cytoplasm of that cell. (N:C)
When does the third cleavage take place in human zygote after fertilisation?
72 hours
What type of cleavage is the first cleavage in human zygote?
Meridional
What type of cleavage is the second cleavage in human zygote?
Meridional at right angle to the first cleavage
What type of cleavage is the third cleavage in human zygote?
Equatorial
What kind of cleavage do humans show?
Holoblastic rotational and indeterminate cleavage
What is indeterminate cleavage?
Fate of blastomeres is decided after 8-celled stage (morula)
On which axis does the meridional cleavage take place?
On the longitudinal axis from animal pole to vegetal pole
Holoblastic cleavage takes place in which type of eggs (on the basis of amount of yolk)?
Alecithal, microlecithal, mesolecithal
Meroblastic cleavage takes place in which type of eggs (on the basis of amount of yolk)?
Megalecithal
Discoidal meroblastic cleavage is found in which animals?
Birds, reptiles
Superficial meroblastic cleavage is found in which animals?
Insects
What is bilateral cleavage of zygote?
Only meridional cleavage takes place
What type ofcleavage occurs in cephalopods?
Bilateral cleavage
WHat type of cleavage occurs in protostomes?
Spiral cleavage
What type of cleavage occurs in deuterostomes?
Radial cleavage
What makes rotational cleavage different from other types of cleavage?
It has a transient 3-celled stage
Where is the morula present?
Fallopian tube
What is the difference between the zona pellucida of morula and blastocyst?
Morula-Zona pellucida intact
Blastocyst- zona pellucida ruptures during maturation
At which cell stage does uterine milk seep into blastocyst?
32 cell stage
How does the blastocoel form in blastocyst?
By seeping in of uterine milk
At which cell stage does the blastocyst hatch?
64 to 128
Why does the zona pellucida rupture in blastocyst?
Due to trophoblastic enzymes
How many days from fertilization does it take for implantation of blastocyst?
7 days
Which layer of embryo prevents immature implantation of embryo? What can its immature rupturing cause
Zona pellucida
Ectopic pregnancy
Name the layers the trophoblast of blastocyst is divided into.
Cytotrophoblast
Syncitiotrophoblast
WHat is cytotrophobast of blastocyst?
Inner cellular layer of trophoblast
What is syncytiotrophoblast of blastocyst?
Outer multinucleated layer
What do the chorionic villi of blastocyst connect with to form placenta?
Decidual crypts
Which layer of blastocyst secretes human chorionic gonadotrophin?
Trophoblast
What is the role of hCG in pregnancy?
Acts like LH and maintains corpus luteum for first trimester of pregnancy
Which hormone is known as pregnancy hormone
Progesterone
What is coeloblastula?
Hollow blastula
What is stereoblastula?
Solid blastula
What does the hypoblast layer of blastocyst form?
Embryonic endoderm
Which layers of blastula form the chorion?
Cytotrophoblast + extra embryonic mesoderm
What form amnion in blastula?
Extraembryonic mesoderm +epiblast/ectoderm
What prevents human embryo from desiccation?
Amnion
What form yolk sac in human embryo?
Extra-embryonic mesoderm + endoderm/hypoblast
What is the function of yolk sac in humans?
Haemopoietic
Forms male and female germ cells
What form alantois?
Extra-embryonic mesoderm + endoderm (hypoblast)
What is known as urinary bladder of embryo of birds and reptiles?
Allantois
What is the function of allantois in human embryo?
Forms umbilical cord blood vessels and wharton’s jelly
Where does the primitive streak appear in blastula?
On dorsal surface of epiblast
What is the function of primitive streak in blastula?
Decides embryonal axis and bilateral symmetry
Which layers is the source of all germ layers in blastula?
Epiblast
Which layer of blastula has prospective mesodermal and endodermal cells?
Epiblast
Which cells get incorporated with hypoblast to form endoderm?
Prospective endodermal cells of epiblast
What does the primitive node turn into in embryo?
Hensen’s node
What does the hensen’s node of embryo have?
Prospective mesodermal cells
What do the prospective mesodermal cells of embryo form?
Notochord
Which is the first organ formed in an embryo?
Heart
Which is the first organ system formed in emryo?
Nervous system
What is the ectodermal region which forms nervous system called?
Neural plate
What forms the central nervous system in embryo?
Neural tube
What forms the peripheral nervous system in embryo?
Neural crest
What are the six possible maternal and fetal barriers of placenta?
Maternal endothelium, connective tissue, ectoderm
Fetal endothelium, connective tissue, ectoderm
What is epitheliochorial placenta?
Placenta in which all 6 maternal and fetal barriers are present
What is syndesmochorial placenta?
Placenta in which 5 barriers are present, maternal epithelium is broken
What in endothelialchorial placenta?
Placenta in which 4 barriers are present, maternal epithelium and maternal connective tissue are lost
WHat is hemochorial placenta?
Placenta in which only fetal barriers are present, maternal blood bathes fetal chorion
What is hemoendothelial placenta?
Placenta in which only one barrier- fetal endothelium is present
Which type of placenta on the basis of number of placental barriers is found in humans?
Hemochorial placenta
Which type of placenta on the basis of number of placental barriers is found in horse?
Epitheliochorial placenta
Does allantois form placenta in humans?
No, human placenta has chorion only
What is non deciduate placenta?
Only fetal part of placenta is delivered
What is deciduate placenta?
Both fetal and maternal part of placenta are delivered
What is central decidual placenta?
Both fetal and maternal part of placenta are not delivered
What is diffused placenta?
Chorionic villi are uniform in distribution
What is cotyledonary placenta?
Chorionic villi form clusters
What is intermediate placenta?
Both diffused and cotyledonary type
What is meta discoidal placenta?
Chorionic villi were diffused initially, later form clusters
What is discoidal placenta?
Chorionic villi arranged in disc shape
What is embryo called after 8 weeks?
Foetus
In which month does the foetus have the maximum growth rate?
4th month
What effect does smoking have on foetus of pregnant mother?
Cleft lip and cleft plate
What gives the first stimulus for parturition? What is the stimulus?
Fetus
Prostaglandin F
What gives the second stimulus for parturition? What is the stimulus?
Placenta
human Chorionic corticotrophin (hCATCH)
What are the three stages of parturition?
Dilation stage
Expulsion (of fetus) stage
Shedding of the placenta
What part of fetus comes out first during parturition?
Head
What causes the shift of placental ventilation to pulmonary ventilation in infant?
Nitric oxide
How does placenta provide immunity to fetus?
Via IgG antibodies
What is the function of human chorionic thyrotrophin?
Stimulates maternal thyroid gland to increase thyroid hormone release
What is human chorionic somatomammotropin also known as?
Human placental lactogen
When is the peak of relaxin hormone from time of fertilization?
14th week and time of delivery
Which vessels are present in the umbilical cord?
2 arteries and 1 vein
Which blood does the umbilical artery carry?
Deoxygenated blood
Which blood does the umbilical vein carry?
Oxygenated blood
Is the blood in umbilical vessels fetal or maternal?
Fetal
