Talk:BGDA Practical - Fertilization to Implantation

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BGDA Practical - Fertilization to Implantation Interactive

Oogenesis Interactive Component

Attempt the Quiz - Oogenesis and Ovulation 

Here are a few simple Quiz questions that relate to Oogenesis and Ovulation from the lecture and practical.



Oogonia divide by mitosis

During the fetal period.
After birth.
After puberty.
During the reproductive period.
All of the above.


Oocytes in follicles enter prophase 1 of meiosis and are arrested at the diplotene stage. Which of the following block the further stages of mitosis?

follicular stimulating hormone (FSH)
leutenising hormone (LH)
cyclic AMP (cAMP) secreted by follicles


Which of the following is the most correct sequence of ovarian follicle development classifications.

Preovulatory, Secondary, Primary, Primordial
Graafian, Primary, Small antral, large antral
Primordial, Primary, Secondary, Preovulatory
Primary, Secondary, Preovulatory
None of the above

Gametogenesis Interactive Component

Attempt the Quiz - Gametogenesis 

Here are a few simple Quiz questions that relate to Gametogenesis from the lecture and practical.



During Prophase I of meiosis:

Reduction of the number of chromosomes occurs
random recombination of hereditary material (DNA) occurs
already duplicated DNA is separated
nondisjunction of the chromosomes could occur
All of the above.


In meiosis, the composition of chromatid is changed during:

prophase I
metaphase I
anaphase I
anaphase II
prophase II


In a dividing cell, the replication of DNA occurs during:



Which of the following would be the most common karyotype for Turner's Syndrome:


Fertilization Interactive Component

Attempt the Quiz - Fertilization 

Here are a few simple Quiz questions that relate to Fertilization from the lecture and practical.



At fertilisation:

male and female pronuclei complete their meiotic division
male and female pronuclei enter interphase
cyclic AMP (cAMP) is secreted by the zygote to block polyspermy
the zona pellucida is discarded
All of the above.


All of the following are essential for successful fertilization except:

capacitation of the sperm
transport of the sperm through the female genital tract
transport of the zygote to the uterine cavity
separation of the sperm from semen
bidirectional movements of gametes in the uterine tube


Fertilization commences when a spermatozoon makes contact with an oocyte and ends:

with the intermingling of maternal and paternal chromosomes at metaphase of the first cleavage division
when the spermatozoon is completely taken into the ootid
when the spermatozoa penetrates the zona pellucida
with the formation of the second polar body
all of the above


Transport of sperm through the cervix is assisted by all of the following except:

capacitation of the sperm
the time of the female cycle
properties of the cervical mucus
contractile activity of the uterus

{Select the correct options below that refer to the maternal contributions to the zygote:


+ mitochondria + nucleolus + one centriole - Y chromosome - polar bodies

Y chromosome is a paternal contribution. The polar bodies do not contribute to the zygote, they are extruded and lost after this first cell stage.

Early Cell Division Interactive Component

Attempt the Quiz - Early Cell Division  

Here are a few simple Quiz questions that relate to Early Cell Division from the lecture and practical.

Not quite ready yet. Come back again after the practical for this quiz!



The zona pellucida is present around:

a primary oocyte
a secondary oocyte
the morula
an early blastocyst
all of the above


Which of the following is the correct sequence during the first week of development:

zygote, blastocyst, blastomeres, morula
zygote, morula, blastocyst, blastomeres
zygote, blastomeres, morula, blastocyst
zygote, morula, blastomeres, blastocyst
none of the above


Which part of the morula is the region with the most rapidly dividing cells:

the inner cell mass
the trophectoderm
the apical polar region
the outer cells
the inner cells


Which cellular part of the blastocyst is mainly involved with the zona pellucida "hatching" process:

the inner cell mass
the trophectoderm
the embryoblast
the blastocoel
none of the above

Interactive Component

Attempt the Quiz - Implantation 

Here are a few simple Quiz questions that relate to Implantation from the lecture and practical.



Which of the following is essential for successful implanatation?

a decidual reaction
transport of the blastocyst to the uterine cavity at the right time
removal of the zona pellucida just before attachment of the blastocyst
release of Prostaglandin E2 by the endometrial stroma
all of the above are needed


Diagnostic tests for pregnancy are based mainly on:

levels of oestrogens
levels of progesterone
levels of thyroxin
secretion of human chorionic gonadotrophin (hCG)
secretion of human chorionic somatomammotropin (hCS)


During implantation of the blastocyst:

usually implants in the posterior wall of the uterus
release substances that cause local changes in the endometrial tissue
attaches itself to the endometrium at its embryonic pole
implantation can occur anywhere within the uterus or uterine tube
all the above are correct


Implantation normally takes place in the:

cervical region
two-thirds lateral uterine tube
body of the uterus, most frequently on the anterior wall
body of the uterus, on the posterior wall
peritoneal cavity

Week 2 Interactive Component

Attempt the Quiz - Week 2 

Here are a few simple Quiz questions that relate to Week 2 from the lecture and practical.



The decidua that takes part in the formation of the maternal component of the placenta is:

the decidua basalis
the decidua capsularis
the decidua parietalis
the villous chorion
the smooth chorion


The usual site of ectopic pregnancy is the:

abdominal cavity
uterine tube
cervix of the uterus
external surface of the uterus


Which of the following statements is most correct:

A partial hydatidiform mole is a conceptus with only paternal chromosomes.
A complete hydatidiform mole is a conceptus with only paternal chromosomes.
Triploidy is generated by an oocyte not completing meiosis and then fertilised by one sperm.
Hydatidiform moles are easily identified as they do not produce hCG.
Hydatidiform moles cannot be identified by ultrasound and require other diagnostic tests.


Which of the following statements about week two (GA week 4) of development are incorrect:

This is the period of implantation into the wall of the uterus.
Pregnancy from blastocyst hatching after this week occur in 50% of births.
Implantation during this week can occur anywhere within the uterus body.
hCG from trophoblast cells enters the maternal blood stream through uterine blood vessels.
The inner cell mass now differentiates into two distinct cellular layers.

these below are currently empty.

Extraembryonic Spaces Interactive Component

Attempt the Quiz - Extraembryonic Space 

Here are a few simple Quiz questions that relate to Extraembryonic Spaces from the lecture and practical.

Not quite ready yet. Come back again after the practical for this quiz!

   Syntax error


The extra-embryonic coelomic spaces are the:

blastocoel, previtelline space and villous chorion
decidua parietalis, decidua basalis and decidua capsularis
pericardial, pleural and peritoneal
smooth chorion, villous chorion and amnion
amnion, chorion and yolk sac


The trophoblast differentiate to form part of the:

outer cell mass
none of the above


The yolk sac proper:

is limited by the exocoelomic membrane
is formed by separation of teh ctyotrophoblastic layers
disappears after the third week
is lined by endodermal cells
none of the above

Back to Online Class


Understand key events in human development from gametogenesis, to fertilization and implantation.

Key Concepts

Gonad, gametogenesis, ovary, oocyte, sperm, meiosis/mitosis, follicle, ovulation, zona pellucida, polar bodies, hormonal changes, mechanism of fertilization, post-fertilization changes, corpus luteum, zygote, morula, blastocyst, zona pellucida, embryoblast, trophoblast, ectopic implantation, abnormalities.

Key Reading

  1. Schoenwolf, G.C., Bleyl, S.B., Brauer, P.R. and Francis-West, P.H. (2009). Chapter 1, 2, and 3 in Larsen’s Human Embryology (4th ed.). New York; Edinburgh: Churchill Livingstone..
  2. Moore, K.L. & Persuad, T.V.N. (2008). Chapter 1 and 2 in The Developing Human: clinically oriented embryology (8th ed.). Philadelphia: Saunders.

Online Resource


Fertility and infertility issues are a common clinical topic and a scientific knowledge of this process is vital for your ability to explain key concepts to patients. This is also an area where scientific research is still making great clinical changes in regulating fertility (birth control), infertility (in vitro fertilization) and prenatal diagnosis (invasive/non-invasive testing). Note that fertility, infertility, genetic testing and stem cells are key current ethical and legal topics.

The generation of gametes (haploid) in the ovary (oocyte, egg) and testis (spermatozoa) and their coming together at fertilization (diploid) and the early events that follow are the focus of this practical class.

Fertilization occurs during the normal female menstrual cycle and the first 1 to 2 weeks of development occur without implantation within the uterus and only implantation can stop the menstrual cycle. Fertilization is a highly regulated biological process combining two different genetic backgrounds in a unique new combination with future postnatal health ramifications. Due largely to the timing, birth control, genetic and uterine abnormalities most fertilization events will not continue to develop into an embryo and will be lost. Note also that it is during these first 2 weeks that both embryonic stem cells are available and twinning events can occur.

Implantation of the conceptus leads to maternal and embryonic changes that include the development of a specialized shared organ, the placenta. These topics will be covered in other lectures and practicals. Only abnormal implantation events will be covered in this current practical.

The practical class will work through a series of online materials that cover gametogenesis, fertilization and implantation. The online materials alone are sufficient to cover the topic at this current level, additional content and resources are provided as links on each page. Make sure to construct your own notes and resources during the practical and attempt the linked Quiz when you have finished in your own time.


  1. All events that occur from gametogenesis to implantation cannot be covered in depth in today’s two hours class. All practical material is available online and content is permanently available through the web, as are the additional resources.
  2. All timings are only approximate and refer to embryonic days from fertilization (post–fertilization age) and not the clinical measurement from Last Menstrual Period (LMP) or gestational age (GA).
  3. Some of the later implantation events will also be revised in the Embryology class (Practical 6) so today mainly focuses on the earlier events.
  4. Consider also the maternal changes that occur during this period, that commence after fertilization with implantation (week 2). This will be also covered in the Fetal Membranes class (Practical 8).
  5. Other Anatomy classes cover anatomy and histology of the gonads and uterus will been covered in
  6. For the new terms introduced in the class use the linked glossary (A - Z found at the bottom of each page) or the search window (at the top of each page).

Back to Online Class


2010 Practical Audio

Mark Hill.jpg

BGD Cycle A 2010 Audio - Dr Mark Hill Monday 12th May 2010 12-2pm G2G4.

Note - this is a live unedited recording from the practical and may contain errors in either descriptions or content.

listen Part 1 | download (356 Kb MP3 2:45)

Developmental Biology

Developmental Biology 6th edn.png Citation: Developmental Biology, 6th ed., Gilbert, Scott F; Sunderland (MA): Sinauer Associates; 2000. ISBN-10: 0-87893-243-7

More general development textbook edition is freely available online through NCBI Bookshelf.

Links: 6th Edition NCBI Bookshelf | 9th Edition Website | 9th Edition Website