Embryology I: General Embryology Study Aid 8/10/2010 Nickalus Khan
Questions (1-70)
1.
What type of division involves replication of cells without reduction of number of chromosome number?
2.
What type of division involves reduction of chromosome number?
3.
What is the normal complement of chromosomes in a cell?
4.
What happens in the S phase of mitosis?
5.
In what phase of mitosis is a chromosome first visible microscopically?
6.
In what phase of mitosis do microtubules line up chromosomes on a plate?
7.
In what phase of mitosis do sister chromatids separate?
8.
What phase of mitosis involves the constriction furrow?
9.
What is the chromosome # in the stage that involves the constriction furrow?
10.
Why is prophase longer in meiosis than mitosis?
11.
What occurs in prophase of meiosis that involves genetic recombination?
12.
How is metaphase I different in meiosis than in mitosis?
13.
After Meiosis I how much DNA is present? How many chromosomes?
14.
After Meiosis II how much DNA is present? How many chromosomes?
15.
In metaphase II what is pulled apart?
16.
From each spermatogonia how many spermatids are developed?
17.
From each oogonia how many oocytes are developed?
18.
What is a polar body? What is its ultimate function?
19.
What makes up the head of a spermatozoa?
20.
What cellular compartment is the acrosomal layer that is draped over the head of the spermatozoa derived from?
21.
What is the function of the layer discussed in question 20?
22.
Why is mitochondrial inheritance maternally derived?
23.
What is the acellular membrane around oocyte that persists until fertilization occurs?
24.
Collectively, what are the cells around the oocyte referred to as?
25.
At what point of meiosis is a primary oocyte arrested ?
26.
At what point of meiosis is a secondary oocyte arrested?
27.
What portion of the oviduct does fertilization occur in?
28.
What is a sperm covered with that prevents fertilization?
29.
What is the process of removal of the answer to #28?
30.
In order for the sperm to penetrate the zona pellucid what must occur?
31.
What causes the oocyte, once penetrated by one sperm, to prevent other sperm from entering
(polyspermy)?
32.
What are the three consequences of fertilization mentioned in lecture?
33.
When cells undergo compaction and reach the 16 cell stage what is the embryo referred to as?
34.
At what stage does the embryo arrive in the uterus?
35.
When fluid begins to leak through the zona pellucid and forms a cavity what is the embryo called?
36.
What are the two layers of the bilaminar disk?

Embryology I: General Embryology Study Aid 8/10/2010 Nickalus Khan
37.
What does the outer cell mass form?
38.
What layer of the trophoblast invades the endometrium to get nutrients and blood?
39.
What produces beta-hCG?
40.
When can beta-hCG be detected?
41.
What is a method to detect pregnancies earlier?
42.
What is a pregnancy that occurs in the wrong place called?
43.
Where do most ETP’s occur?
44.
What is an ETP called in the cervical canal?
45.
What is the most likely place for an ETP in the peritoneal cavity?
46.
What forms the primary yolk sac?
47.
What fills the space between primary yolk sac and cytotrophoblast?
48.
What is extraembryonic mesoderm called around the yolk sac?
49.
What is the fetal part of the placenta derived from?
50.
Maternal part of placenta derived from?
51.
What week does gastrulation occur?
52.
What is the area in which the epiblast and hypoblast are tightly ajoined?
53.
What do the cells that travel through primitive pit toward buccopharyngeal membrane form?
54.
What cells migrate in the bilaminar disk to form endoderm and mesoderm?
55.
What connects the primitive pit and yolk sac?
56.
What is the remnant of the notochord in the intervetebral disk?
57.
What is a abnormal remnant of the primitive streak?
58.
What forms the epiblast over the notochord?
59.
What forms from General ectoderm?
60.
What forms from neurectoderm?
61.
What forms from neural crest?
62.
What forms from endoderm?
63.
What forms from mesoderm?
End of Class questions (2 will be on exam)
64.
The developing embryo reaches the uterus as a _________ (indicate stage of development).
65.
Before sperm can fertilize an egg, they must remain in the female reproductive tract for approximately 7 hours during which they undergo a process known as ________.
66.
When a sperm is taken inside the egg, the egg plasma membrane is rendered impenetrable to any other sperm. This block to polyspermy is cause by _________.
67.
Gastrulation causes the establishment of what germ layers?
68.
Cell destined to become the notochord migrate through the __________.
69.
The loss of what structure from the embryo permits implantation to begin?
70.
Indicate the states of chromosome number and DNA content in division of products after the first meiotic division.

Embryology I: General Embryology Study Aid 8/10/2010 Nickalus Khan
Answers:
1.
2.
7.
8.
9.
3.
4.
5.
6.
Mitosis
Meiosis
2N (diploid)
Duplication of DNA (still same # of chromosomes, just sister chromatids=4d)
Prophase
Metaphase
Anaphase
Telophase
2N, remember it is 2N throughout mitosis.
10.
To allow homologous chromosomes to pair
11.
Crossing over
12.
Pulls chromosomes apart, it is a reduction division (2N  N)
13.
2d, N
14.
D, N
15.
Sister chromatids (similar to mitosis), differentiate this from what happens in metaphase I
16.
4
17.
1
18.
Result of unequal division of cytoplasm in oogenesis, undergoes apoptosis and degenerates
19.
Nucleus
20.
Golgi apparatus (acrosomal layer is draped over head)
21.
Provides enzymes necessary for fertilization.
22.
Because the mitochondria in the sperm are located in the tail of spermatid and degenerate  all mitochondria come from mother
23.
Zona pellucida
24.
Corona Radiata
25.
Diplotene of prophase I, until puberty occurs at which point it completes Meiosis I and a secondary oocyte is ovulated each month
26.
Metaphase of Meiosis II until fertilization occurs at which point it forms an embryo (therefore there really is no such thing as a mature ovum)
27.
Distal 1/3 of oviduct
28.
Protein coat
29.
Capacitation, typically takes 7 h
30.
Acrosome reaction, Enzymes are released and the plasma membrane over the acrosome is dissolved  hole is made in zona pellucid to allow for passage of sperm
31.
Cortical reaction
32.
Restoration of chromosome #, Sex determination, initiation of cleavage
33.
Morula
34.
As a morula
35.
Blastocyst (these are the pluripotent stem cells everyone is talking about), blastocyst sticks to uterine wall which has been prepared via hormonal changes

Embryology I: General Embryology Study Aid 8/10/2010 Nickalus Khan
36.
Epiblast, Hypoblast (remember- week 2 has 2 layers)
37.
Cytotrophoblast, Syntrophoblast
38.
Syntrophoblast
39.
Syntrophoblast
40.
8-11 days post fertilization
41.
Early pregnancy factor (EPF) which has to do with an immunologic factor protecting fetus from mothers immune system early on
42.
Ectopic pregnancy, previous pelvic infections cause adhesions which can lead to these
43.
Distal portion of oviduct
44.
Placenta previa
45.
Rectouterine pouch (pouch of douglas)
46.
Migrating cells from hypoblast
47.
Extraembryonic somatic mesoderm (this also forms the secondary yolk sac due to its migration pattern)
48.
Splanchnic extraembryonic mesoderm
49.
extraembryonic mesoderm, cytotrophoblast, syntrophoblast
50.
Decidua basalis (lining of uterus)
51.
Week 3 (remember, 3 layers –ectoderm, endoderm, mesoderm in 3 rd week)
52.
Buccopharyngeal membrane (future site of mouth-prochordal plate)
53.
Notochord
54.
Epiblast cells migrate downward to form endoderm and mesoderm, the epiblast cells that remain in the epiblast form ectoderm
55.
Neurecentric canal
56.
Nucleus pulposus
57.
Sacrococcygeal teratoma
58.
Neurectoderm (neural crest branches off from this in development)
59.
Epidermis of skin, outer covering of teeth, sensory part of inner ear, pituitary gland, mammary gland, lower anal canal
60.
Think CNS and retina! (CNS and Retina

CN II (optic n. which is an outpouching of the brain  CNS)

Neurohypophysis (Portion of pituitary derived from brain..secretes ADH, oxytocin)

Astrocytes (supporting cell in brain)

Oligodendrocytes (myelinates cells of CNS)
61.
Nervous system not from CNS, (ANS…etc.)







Melanocytes (pigment cells)
C cells (secrete calcitonin)
Aortiocopulmonary septum (divides pulmonary trunk and aorta)
Adrenal Medulla (modified ANS ganglion  secretes catecholamines)
Schwann Cells (myleinates peripheral nerves)
Odontoblasts (teeth formers)
ANS

Embryology I: General Embryology Study Aid 8/10/2010 Nickalus Khan
62.




Lining of GI tract, Respiratory tract
Bladder, Rectum
Pharyngeal Pouches
Parenchyma of liver, pancreas, sublingual, submandibular, thyroid gland
63.


Muscle
Connective tissue of: a) Kidney b) Liver c) Spleen d) Cardiovascular e) Gonads
64.
Morula
65.
Capacitation
66.
the release of lysosomal enzymes by cortical granules
67.
endoderm, mesoderm, ectoderm
68.
primitive pit
69.
Zona pellucida
70.
2d DNA and n chromosomes