Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Obstetrics > Gametogenesis ➡️ Fetus > Flashcards

Gametogenesis ➡️ Fetus Flashcards

1
Q

Germ cells are derived from

A

Epiblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

When Germ cells migrate to yolk sac ?

At 6wks of pregnancy germ cells migrate to?

A

3 wks of preg

Gonadal ridge in 6 wks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Germ cells are bipotential till?

Gene to determine sex of fetus

A

6wks

SRY gene on short arm of Y chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Difference between spermatogenesis and spermiogenesis

A

Spermatogonia ➡️ Sperm

Spermatid ➡️ Sperm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Spermatogenesis begins at?

Oogenesis begins at

A

Puberty

Intrauterine life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Parts of spermatid

A

Acrosomal cap ⬅️ Golgi body
Head⬅️ nucleus
Middle piece⬅️mitochondria
Tail⬅️ centriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Organalle lacked by sperm

Arrangement of centriole in tail

A

Rough ER

9+2 arrangement of filament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Site of spermatogenesis

Time for spermatogenesis

A

Seminiferous tubule

Puberty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does a sperm attains maturity and motility

A

Caudal end of epididymis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Gene for motility of sperm

Ion for motility

A

CATSPER

Ca+2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Time taken for sperm to reach ampulla of fallopian tube

Sperm remains motile in fgt for?

A

30 min

12hrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

FSH acts on? During spermatogenesis

Negative feedback to decrease fsh is given by

A

Sertoli cells

Inhibin B released by sertoli cells
And indirect by testosterone by inhibiting GnRH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Blood testis barrier is formed by

A

Sertoli cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

1st stimulus for testis to produce testosterone

A

hcg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Primary oocyte gets arrested in which stage

A

Diplotene stage of prophase 1 during meiosis 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is primordial follicle

A

Primary oocyte surrounded by follicular cells ie granulosa and theca cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is ovulation

A

It is release of secondary oocyte from primary oocyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Female pronucleus is formed by

A

Secondary oocyte undergoes meiosis 2 but arrested in metaphase till fertilization
When fertilization takes place secondary oocyte changes to female pronucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Follicles present during 5 month of IUL
At birth
At puberty

A

7 million follicles (max)
1-2 million
4lakhs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is dictyate stage

Where is it absent

A

Arrested stage of of primary oocyte in first meiosis

It is absent in spermatogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Sequence of events before fertilization

A

Capacitation
Acrosomal reaction
Cortical reaction
Zona reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Function of zona pellucida

A

It prevent polyspermy when one sperm reaches zona

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is cortical reaction and zona reaction

A

Cortical reaction-When sperm reaches perivitelline space it touches ooplasm and cortical granules release enzyme
Zona reaction- the enzymes make zona pellucida impermeable to other sperms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Capacitation is

Where does in occurs mainly

A

Ability of sperm to fertilize ova
Takes place in fgt
Mainly occurs at fallopian tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Fertilization occurs in

A

Ampulla of fallopian tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Function of zona pellucida in a zygote

A

It will not allow zygote to implant in fallopian tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Morula is

A

8-16 celled zygote surrounded by zona pellucida

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Types of cell in fallopian tube

A

Ciliated columnar cell - push zygote to uterine cavity by peristalsis
Secretory cells nutrition to early zygote
Peg cells unknown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What happens during implantation if progesterone contraceptive failure occurs

A

progesterone is smooth muscle relaxant

Contraceptive failure leads to ectopic pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Implantation takes place on day?

A

Day 5 of fertilization

31
Q

Process of implantation occurring on uterine cavity

A

Zona pellucida sheds (Zona Hatching)
Morula ➡️ Blastocyst as fluid enters
Blastocyst attaches to uterine cavity

32
Q

Implantation occurring deep inside endometrium

What structure prevents implantation in myo or serosa

A

Interstitial implantation

Nitabuch layer

33
Q

Phases of implantation.

Which of these is morphological marker of endometrial receptivity and implantation

A

Apposition
Adhesion
Invasion

Apposition facilitated by pinopods

34
Q

Piskacek sign
Hartman sign
Intradecidual sign

A

Assymetrical growth of uterus in early pregnancy

Bleeding at the time of implantation

Blastocyst implants deep into endometrium

35
Q

Division of decidua

A

Decidua basalis
Capsularis
Parietalis

36
Q

Site of formation of future maternal side of placenta

A

Decidua basalis

37
Q

When does uterine cavity gets obliterated

A

By 14-16 wks

38
Q

2 ova fertilized by 2 sperm in same cycle

A

Superfecundation

39
Q

Double decidual sac/ring sign the blastocyst surrounded by

A 
decidua capsularis (inner ring) 
Decidua parietalis (outer ring)
40
Q

Trophoblast is divided into

A

8 days after fertilization Trophoblast is divided into

Cytotrophoblast(langhans cell layer) and syncytiotrophoblast (multinucleated syncytium)

41
Q

Embryonic disc is formed by

A

5 cells from inner cell mass of blastocyst out of 58cells

42
Q

Function of cytotrophoblast

A

Retains its cell boundaries and divides into villous and extravillous cytotrophoblast

43
Q

What is chorion frondosum

A

It is fetal side of placenta

Villous cytotrophoblast forms villi like str near decidua basalis

44
Q

Rest of villous CT forms?

A

It remains smooth and is ka chorion laeve

45
Q

What is trophoblastic invasion?

A

Non villous CT divides into endovascular CT and interstitial CT
Endovascular CT replace lining of maternal spiral artery which open in IVS to convert high resistance vessels to low resistance

46
Q

When does trophoblastic invasion occurs

What happens if it doesn’t happen?

A

Occurs in 2 steps
First wave- 12 wks
Second wave - 16 wks

If trophoblastic invasion doesn’t happen it leads to
UPI
PIH
IUGR

47
Q

What is known as hormone factory of placenta

A

Syncytiotrophoblast -it rises from CT but doesn’t retains their cell boundaries

48
Q

Embryonic disc divides blastocyst cavity into

A

Amniotic cavity and yolk sac

49
Q

Amniotic cavity is lined by
Yolk sac is lined by
Primitive streak forms

A

Ectoderm ( third germ layer)

Endoderm (first germ layer)

Mesoderm (second germ layer)

50
Q

Amniotic cavity and yolk sac is seen on usg as

A

Double bleb sign

51
Q

Curving of caudal and cranial end of embryonic disc is seen as? ( on usg)

A

Embryonic poles on usg

52
Q

Distance between two embryonic poles

A

Crown rump length

53
Q

Hearts starts beating on

A

Day 21 after fertilization

54
Q

When is this str seen on TVS
Gestational sac
Yolk sac
Cardiac activity

A

4 wk1 day to 4 wk 3 day

4wk 5 day

5-6 wks

55
Q

First fetal str seen on usg

A

Gestational sac

56
Q

What is critical value of beta hcg in Tvs and tas

A

If beta hcg is more than or equal to 2000IU/L in intrauterine pregnancy gestational sac is visible on TVS
In TAS -6500 IU/L

57
Q

Case
A pregnant female with beta hcg more than 2000Iu/L
Gestational sac not visible on TVS
Probable diagnosis

A

Ectopic pregnancy

58
Q

A pregnant female with beta hcg less than 2000 IU/L
NO gestational sac visible on TVS
Next step?

A

Repeat beta hcg after 48 hrs
If doubles ➡️ intrauterine
If increases but not doubles ➡️Ectopic

59
Q

If MSD > equal to 10 mm and no yolk sac is seen

What can be the cause

A

Pseudogestational sac of ectopic pregnancy

60
Q

What is blighted ovum (anembryonic pregnancy)

A 
MSD more than 25mm 
Yolk sac present
No fetal tissue
No CRL
No cardiac activity
61
Q

Characterstic of human placenta

A

Discoid - disc like
Hemochoroidal -lies in contact with maternal blood
Deciduate -sheds off after delivery

62
Q

Weight of placenta at term
Ratio of weight of placenta to fetus
When is wt of placenta= wt of fetus

A

500g
1:6

At 17wkd of pregnancy

63
Q

Cells of placenta

Which virus infects this cell

A 
Hofbauer cells (macrophage) 
Zika virus can infect hofbauer cell to allow fetal transmission
64
Q

Str separating maternal blood from fetal blood

A

Syncytiotrophoblast
Cytotrophoblast
Extraembryonic mesoderm
Fetal capillary endothelium

65
Q

Primary villi
Secondary villi
Tertiary villi

A

Primary- trophoblastic shell
Secondary- + extraembryonic mesoderm (mesodermal core)
Tertiary — (vascular) fetal blood capillary in villi

66
Q

Timeline for formation of villi after fertilization

A

Primary -day 13 after fertilization
Secondary villi- day 16 after fertilization
Tertiary - day 17 after fertilization

67
Q

When does maternal spiral artery opening into IVS

A

Day 15 after fertilization

68
Q

When does fetoplacental circulation is established

A

Day 17 after fertilization

69
Q

Diff bw anchoring and stem villi

A

Anchoring- tertiary villi reaches upto decidua plate

Stem - main tertiary villi from which branch arise

70
Q

Maternal blood in placenta
fetal blood
Volume of placenta at term

A

150 ml
350ml
500 ml

71
Q 
Number of spiral artery opening into intervillous space 
O2 saturation in intervillous space
Partial pressure in ivs
Uteroplacental blood flow at term
Uterine blood flow at term
A 
120 
65-75%
30-35 mm hg 
500-750 ml/min 
750ml/min
72
Q

Fetoplacental flow at term
Fetal blood flow at term
Rate of O2 delivery to fetus

A

400ml/min
125ml/kg
8ml/kg/min

73
Q

Fetoplacental circulation is via

A

Umbilical artery -deoxygenated blood
Fetus to placenta
Umbilical vein- oxygenated blood
Placenta to fetus

Obstetrics (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions