ESHRE-Exam Samples

Question 1

1. Amino acids are linked to the next amino acid in the sequence of a protein by which of the following bonds?
   
   1. Hydrogen
   2. Ester
   3. Glycosidic
   4. Peptide

Answer 1

4.

Question 2

The process of meiosis in the germline starts:

1. During fetal life in males
2. At puberty in females
3. At puberty in males
4. During the first trimester of gestation in females

Answer 2

3,4.

Question 3

Ethylene oxide is commonly used to:

1. Sterilize plastic syringes
2. Sterilize incubators
3. Disinfect benches
4. Disinfect hands

Answer 3

2.

Question 4

pH levels in bicarbonate buffered culture media are:

1. Influenced by the oxygen tension of the air to maintain equilibrium
2. Corrected by other molecules in the culture medium such as amino acids
3. Corrected by partial pressure of CO₂
4. Not only dependent on bicarbonate ions but on other molecules in the culture medium such as amino acids

Answer 4

3.

Question 5

Trophectoderm cells will go on to make parts of the:

1. Fetus
2. Chorionic villi
3. Amniotic sac
4. Uterus

Answer 5

2.

Question 6

Which of following is a valid principle of ice formation?

1. Embryos must be stored at temperatures low enough to allow ice crystals to form
2. Increasing permeability of the cell membrane will prevent ice crystal formation
3. Removing most of the water from the embryo will prevent ice formation
4. Removing too little water will result in increased solute concentration and cell damage

Answer 6

3.

Question 7

One widely used cryoprotectant is:

1. 1.2M 1, 5-Propanediol
2. 1.0M 1, 5-Propanediol
3. 0.5M 1, 2-Propanediol
4. 1.5M 1, 2-Propanediol

Answer 7

3.

Question 8

Advantages of vitrification:

1. Rapid cooling/warming rates
2. Requires no programmable freezer
3. Shortened exposure to cryoprotectants compared to slow cooling
4. All of the above

Answer 8

4.

Question 9

Most Down’s syndrome are due to:

1. Non-disjunction in the oocyte first meiotic division
2. Non-disjunction in the spermatocyte first meiotic division
3. Non-disjunction in the oocyte second meiotic division
4. Non-disjunction in the spermatocyte second meiotic division

Answer 9

1.

Question 10

In PGD for X-linked recessive disease, where the female is a heterozygous carrier, and the male is normal, what proportion of the female embryos will be affected?

1. None
2. 75%
3. 50%
4. 25%

Answer 10

1.

Question 11

The European Tissues and Cells Directives (EUTCD) applied:

1. Only to units that store gametes
2. To units that store gametes and embryos
3. Only to units that store ovarian and testicular tissue
4. To units that handle fresh and frozen gametes, embryos and gonadal tissue

Answer 11

4.

Question 12

What aspect of laboratory operations monitors equipment and processes to ensure that the laboratory is functioning properly on a day to day basis?

1. Documentation
2. Quality improvement
3. Quality control
4. Quality assurance

Answer 12

3.

Quality control

aspect of laboratory operations monitors

equipment and processes

that ► ensure that the laboratory is functioning properly

⇒ on a day to day basis

Question 13

This Day-5 blastocyst is scored according to the Istanbul consensus workshop criteria as:

1. Stage=3 (Expanded), ICM=3 (Poor), TE=2 (Fair)
2. Stage=2 (Blastocyst), ICM=3 (Poor), TE=3 (Poor)
3. Stage=3 (Expanded), ICM=2 (Fair), TE=3 (Poor)
4. Stage =2 (Blastocyst), ICM=2 (Fair), TE=2 (Fair)

Answer 13

1.

blastocyst —-EXPANDED (3)

ICM few cells no compaction-poor (3)

TE fair (2)
= 3CB

Question 14

According to WHO Laboratory Manual for the Examination and Processing of Human Semen (2010), the assessment of sperm morphology must be made in duplicate, evaluating _______ spermatozoa in each replicate.

1. 50
2. 100
3. 200
4. 300

Answer 14

3.

Question 15

Ovarian primordial follicles begin their development:

1. Via a mechanism that is currently incompletely characterised
2. At the end of the preceding ovarian cycle
3. Only after the beginning of sexual maturity
4. In response to gonadotropins

Answer 15

4.

Question 16

Gonadotropin hormones are synthesized in the:

1. Hypothalamus
2. Posterior pituitary
3. Anterior pituitary
4. Gonads

Answer 16

3.

Question 17

Immotile sperm and immotile cilia are a feature of:

1. Kartagener’s syndrome
2. Beckwith-Wiedemann syndrome
3. Kallman’s syndrome
4. Disorders involving mitochondrial DNA deletions

Answer 17

1.

Question 18

Kallmans syndrome

Answer 18

Kallmann syndrome

is a condition characterized by

body does not make enough of (GnRH)

delayed or absent puberty (hypogonadism low FSH and LH)

and an impaired sense of smell.

olfactory disorders

Question 19

A peroxidase stain of semen smears is used to:

1. Differentially stain nuclear and acrosomal regions of sperm head
2. Identify granulocytes
3. Identify sperm cells with fragmented DNA
4. Identify the presence of reactive oxygen species in the semen

Answer 19

2.

Question 20

In humans, implantation involves invasion finally reaching the:

1. Uterine epithelium
2. Endometrial ECM (Extra Cellular Matrix)
3. Basement membrane of endometrial blood vessels
4. Lumen of endometrial blood vessels

Answer 20

3.

Question 21

This is a cross-section of a seminiferous tubule. Which cells do the arrows point to?

1. Spermatogonia
2. Elongated spermatids
3. Primary spermatocytes
4. Sertoli cells

Answer 21

2.

Question 22

1. Embryonic stem cells:
   
   1. Are derived from trophectoderm
   2. Cannot differentiate spontaneously to beating cardiac muscle cells
   3. Can differentiate spontaneously to neural cells
   4. Can be identified as pluripotent by the marker TGF alpha

Answer 22

3.

Question 23

According to the European Directive 2012/39/EU and as far as partner donation of reproductive cells is concerned, the permitted time interval until repeat blood testing is:

1. Up to 24 months
2. Every 6 months
3. Every time the samples are produced
4. Up to 12 months

Answer 23

1.

Question 24

1. Which of the following statements is TRUE?
   
   1. All enzymes are proteins
   2. All proteins are enzymes
   3. Some RNAs are enzymes
   4. Some DNAs are enzymes

Answer 24

1.

all Enzymes are proteins

Prosthetic groups or coenzymes are non-protein

Question 25

**The biggest challenge to cells during freezing is:** 1. Their ability to endure storage at very low temperatures (\< -180ºC) 2. Their ability to endure storage at very low temperatures (\< -360ºC) 3. The lethality of an intermediate zone of temperature (-15ºC to -60ºC) that they must traverse during cooling and again during warming 4. Tolerance to cryoprotectant agents

Answer 25

3.

Question 26

**Vitrified embryos:** 1. Do not contain ice crystals 2. Are completely dehydrated 3. Can be safely stored at -80ºC 4. Can contain ice crystals although less than frozen embryos

Answer 26

1.

Question 27

**The following hormones are secreted by the anterior pituitary:** 1. Growth Hormone, Oxytocin, LH, ACTH 2. Prolactin, Oxytocin, TSH, FSH 3. TSH, ACTH, Prolactin, Growth Hormone 4. LH, ACTH, Antidiuretic Hormone, FSH

Answer 27

3. ## Footnote TSH, ACTH, Prolactin, Growth Hormone► anterior pituitary ---------------------------------------------------------- **posterior pituitary**► Oxytocin & Anti-Deuretic Hormone (ADH)

Question 28

**The process of karyokinesis:** 1. Is dependent on the mitotic spindle 2. Is dependent on the action of actin and myosin filaments 3. Occurs only during the meiotic cleavage 4. Is regulated by protamines

Answer 28

1.

Question 29

Which statement about **light exposure** is **incorrect**? 1. Some spectra of light can generate reactive oxygen species 2. Light damage is related to exposure, wavelength but not intensity 3. Wavelengths \<300nm ultraviolet can be absorbed by plastics 4. 95% radiation is from microscopes

Answer 29

2. ## Footnote all correct except b.

Question 30

An individual with a **balanced translocation**: 1. Always shows evidence of a chromosomal abnormality 2. Invariably passes the translocation on to their child 3. May have a child without the translocation 4. Is unlikely to have fertility problems

Answer 30

3.

Question 31

The genes implicated in **premature ovarian failure** include: 1. SRY and SOX-9 2. AZF and ZFX 3. ZFX and FMR1 4. FMR1 and AMH

Answer 31

**3.** SRY ⇒ Y (SRY - sex-determining region Y = TDF (testis-determining factor) SOX - crucial for male development; genes encoding transcription factors SOX ⇒ AMH/MIH Anti-Müllerian hormone (AMH) AMH - this gene encodes a secreted ligand of the TGF-beta (transforming growth factor-beta) superfamily of proteins Müllerian-inhibiting hormone (MIH) AZF - azoospermia factor on Y chromosome **POF - premature ovarian failure** **ZFX - zinc finger protein on X chromosome; POF** **FMR1 - fragile X mental retardation 1, Parkinson, POF**

Question 32

Which of the following growth factors has been implicated in early follicle **recruitment** and **growth**? 1. GDF-9 (growth differentiation factor 9) 2. BMP-15 (bone morphogenetic protein 15) 3. Kit Ligand (tyrosine kinase receptor Kit (c-Kit)) 4. _All of the above_

Answer 32

**4.** ## Footnote GF involved in Early follicle recruitment and growth (before FSH & LH): GDF-9 (growth differentiation factor 9) BMP-15 (bone morphogenetic protein 15) Kit Ligand (tyrosine kinase receptor Kit (c-Kit))

Question 33

**Regarding genomic imprinting, which of the following statements is true?** 1. Large offspring syndrome in sheep is associated with disrupted *IGF2R* imprinting 2. Erasure of imprints in the preimplantation embryo ensures correct imprinting in each new generation 3. Methylation of imprinted genes is stable in cloned mice but not in cloned sheep 4. PGD screening for *IGF2R* gene imprinting is now routine practice

Answer 33

**1.** IGF2R gene imprinting refers to the process by which certain genes are turned on or off based on whether they are inherited from the mother or the father. -CLinical utility of PGD screening for IGF2R gene imprinting is limited. ## Footnote large offspring syndrome (LOS): a condition that causes the fetus to grow excessively large in the womb. caused by genomic imprinting loss of *(IGF2R)* *Insulin-like growth factor 2 receptor.* may be caused after in Vito culture in sub optimum condition

Question 34

One of the intended purposes of adding EDTA to the embryo culture media is: 1. To avoid ion chelation 2. To inhibit the premature stimulation of glycolysis of the cleavage stage embryos 3. To Favour the embryo development after compaction 4. All of the above are true

Answer 34

2.

Question 35

During **female meiosis:** 1. Meiosis I is completed during fetal development 2. Meiosis II commences during fetal growth 3. Meiosis I is arrested in diplotene during fetal development 4. Meiosis II is arrested in diplotene during fetal development

Answer 35

3.

Question 36

If a semen donor is positive for cytomegalovirus (CMV), then: 1. The donor semen must never be used in treatment 2. The semen may be used for general treatment if the donor is positive only for IgM and not for IgG 3. The specimen should only be used for CMV-positive recipients 4. The specimen may be released for general treatment if the lab has standard operating procedures (SOPs) governing the release of HCT/Ps (Human cellular and tissue products) from CMV-positive patients

Answer 36

4. ## Footnote note: A child after CMV is sick, a dangerous disease. IgM (-) IgG (-) - no infection IgM (+) IgG (-) - fresh infection IgM (+) IgG (+) - the disease is in full swing IgM (-) IgG (+) - virus dormant, acquired immunity

Question 37

**Grade A** air quality, as defined by the Good Manufacturing Practice (GMP) guidelines, is NOT required if: 1. Microbial inactivation or a validated terminal sterilization process is applied 2. It is demonstrated that exposure to the conditions to obtain grade A air has a detrimental effect on the tissue or cells 3. The mode of administration of the tissue or cells implies low or no risk to the recipient 4. All correct

Answer 37

4.

Question 38

**A Gap junction is a type of:** 1. Occluding cell junction 2. Communicating cell junction 3. Anchoring cell junction 4. Dynamical cell junction

Answer 38

* 2. ## Footnote **Occluding cell junctions:** Also known as tight junctions, occluding cell junctions form a barrier between adjacent cells, preventing the movement of molecules and ions across the intercellular space. **Communicating cell junctions:** These junctions, also called gap junctions, allow direct communication and exchange of small molecules between adjacent cells. **Anchoring cell junctions:** Anchoring cell junctions provide structural support and stability to tissues by anchoring cells to each other or to the extracellular matrix. three main types of anchoring cell junctions:(Desmosomes, Adherens junctions, Hemidesmosomes) **Dynamical cell junctions:** Dynamical cell junctions, also known as transient cell junctions, are formed during various cellular processes, such as cell migration, tissue remodeling, and immune response. (Occluding مسدود Anchoring cell junction تماسك structural cohesion of tissues)

Question 39

**Where are the ribosomes produced?** 1. nuclear envelope 2. rough reticulum 3. nucleolus 4. nucleosome

Answer 39

**3.** * Eukaryote ribosomes are produced in the nucleolus. * Ribosomal proteins enter the nucleolus and combine with the four rRNA strands to create the two ribosomal subunits * (one small and one large) that will make up the completed ribosome

Question 40

Somatic cells spend the most amount of time in which phase? 1. interphase 2. prophase 3. metaphase 4. telophase

Answer 40

1.

Question 41

Twenty four hours after insemination by **IVF**, the oocyte on the figure was found to have **7** pronuclei. It is most probably that: 1. It was fertilized by 6 spermatozoa 2. Oocyte chromosomes are dispersed within the ooplasm, are surrounded by nuclear envelopes and form 7 micronuclei 3. The nucleus of the fertilized oocyte divided several times but the cell did not 4. The surplus pronuclei derive from not extruded polar bodies

Answer 41

1.

Question 42

Nucleolar precursor bodies are the sites of: 1. Centromeric DNA synthesis 2. Protein synthesis 3. RNA synthesis 4. None of the above

Answer 42

3.

Question 43

**The biggest challenge to cells during freezing is:** 1. their ability to endure storage at very low temperatures (\< -180ºC) 2. their ability to endure storage at very low temperatures (\< -360ºC) 3. The lethality of an intermediate zone of temperature (-15ºC to -60ºC) that they must traverse during cooling and again during warming 4. tolerance to cryoprotectant agents

Answer 43

3.

Question 44

If cells are frozen slowly, the warming rate must be\_\_\_\_\_\_\_\_\_\_\_\_\_\_; if the cells are frozen rapidly, the warming rate must be \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_: 1. Rapid, in order to give dehydrated cells time to rehydrate and prevent recrystallization; rapid to prevent recrystallization 2. Fast in order to give dehydrated cells time to rehydrate and prevent recrystallization; slow to prevent recrystallization 3. Slow in order to give dehydrated cells time to rehydrate and prevent recrystallization; fast to prevent recrystallization 4. Slow in order to give dehydrated cells time to rehydrate and prevent recrystallization; slow to prevent recrystallization

Answer 44

1.

Question 45

Ovarian primordial follicles were surgically removed from Ms. Z and later transplanted to her abdomen. This is referred to as a(an): 1. Autograft 2. Heterotopic graft 3. Orthotopic graft 4. Xenograft

Answer 45

2. ## Footnote In Vitro Ferilization (K. Elder) Cryopreserved ovarian cortical tissue may be **orthotopically** or **heterotopically** ⇔Both are auto- graft **Heterotopic** sites differ than the normal include the rectus abdominis muscle, the abdominal wall, the breast **Orthotopic site**s of relative tissues include the pelvic peritoneum, the ovary or the ovarian fossa; if the fallopian tubes are intact, natural conception is possible. Xenograft include for example ⇒Experimental xenografting of human testicular tissue in nude mice

Question 46

**Allogeneic use’ means:** 1. cells or tissues removed from one person and applied to another 2. cells or tissues removed from and applied in the same person 3. cells or tissues removed from one person and stored for the same person 4. none of the above

Answer 46

1.

Question 47

Which statement about light exposure is **_incorrect_** 1. some spectra of light can generate reactive oxygen species 2. light damage is related to exposure, wavelength but not intensity 3. wavelengths \<300nm ultraviolet are absorbed by plastics 4. 95% radiation is from microscopes

Answer 47

2.

Question 48

Which of the following describes a type of polymorphism that occurs within the gene that causes Huntington's disease? 1. RFLPs, "restriction fragment length polymorphisms" 2. ESTs, "expressed sequence tags" 3. STRPs, "short tandem repeat polymorphisms" 4. STSs, "sequence tagged sites"

Answer 48

3. ## Footnote Huntington’s disease (HD) is a progressive neuropsychiatric disorder of late onset that is inherited in a **dominant** fashion. The gene is on **chromosome 4** and involves a CAG triplet repeat where expansion beyond 36 results in HD. **STRPs,**"short tandem repeat polymorphisms" polymorphism that occurs within the gene that causes Huntington's disease

Question 49

example of Autosomal, dominant --------------- Autosomal, recessive------------------

Answer 49

Autosomal, dominant - ch. Huntington's. Autosomal, recessive - Tay-Sachs disease (accumulation of fat in the brain).

Question 50

The genes implicated in premature ovarian failure include: 1. SRY and SOX-9 2. AZF and ZFX 3. ZFX and FMR1 4. FMR1 and AMH

Answer 50

3.

Question 51

**Which of the following is a Müllerian abnormality?** 1. Fibroids 2. Polyps 3. Uterine septa 4. Myoma

Answer 51

3.

Question 52

Regarding cell lineages during early embryonic development, the cytotrophoblast and syncytiotrophoblast are derived directly from the: 1. Primitive endoderm 2. Extra-embryonic ectoderm 3. Embryonic ectoderm 4. Extraembryonic mesoderm

Answer 52

b.

Question 53

Regarding genomic imprinting, which of the following statements is true? 1. Large offspring syndrome in sheep is associated with disrupted *IGF2R* imprinting 2. Erasure of imprints in the preimplantation embryo ensures correct imprinting in each new generation 3. Methylation of imprinted genes is stable in cloned mice but not cloned sheep 4. PGD screening for *IGF2R* gene imprinting is now in routine practice

Answer 53

1.

Question 54

The amniotic cavity 1. Appears on Day 6, after blastocyst implantation 2. Is formed by the growth of trophoblast cells 3. Fuses later with the primary umbilical vesicle 4. After the 11-12^th day is surrounded by cells derived from the epiblast

Answer 54

4.

Question 55

Regarding the baseline assessment for endocrinology during an ART treatment cycle, which of the following is correct? 1. Oestradiol \<50 pg/ml, LH \<5 IU/l, Progesterone \<2 ng/ml 2. Oestradiol \<5 pg/ml, LH \<0.5 IU/l, Progesterone \<200 ng/ml 3. Oestradiol \>50 pg/ml, LH \<500 IU/l, Progesterone \<2 ng/ml 4. Oestradiol \<50 pg/ml, LH \>5 IU/l, Progesterone \>2 ng/ml

Answer 55

1.

Question 56

During female meiosis: 1. Meiosis I is completed during fetal development 2. Meiosis II commences during fetal growth 3. Meiosis I is frozen in diplotene during fetal development 4. Meiosis II is frozen in diplotene during fetal development

Answer 56

3.

Question 57

1. SRY, WT1 and SF1 are genes that: 1. Regulate steroidogenesis 2. Are involved in early sexual differentiation 3. Are Y-linked 4. Are X-Linked

Answer 57

2.

Question 58

WNT-4 genes:

Answer 58

involved expression of **steroidogenic enzymes** in the ovary

Question 59

**Wnt-7**

Answer 59

**Expressed in mesodermal layer, in the apical ectodermal ridge** **-distal end of limbs** **Regulate Dorsal-Ventricle Axis**

Question 60

What cell type comprises a **hydatidiform mole?**

Answer 60

trophectodermal placental tissues paternal imprinting

Question 61

Which condition is related to paternal imprinting? A. Accessory placental lobes B. Placenta previa C. Oligohydramnios D. Single umbilical artery E. Hydatidiform mole

Answer 61

E.

Question 62

121. The brain flexure which develops between the metencephalon and the myelencephalon is called the: A. pontine B. hindbrain C. cervical D. cephalic E. midbrain

Answer 62

A. is correct. The pontine flexure occurs between the metencephalon, which forms the pons and cerebellum, and the myelencephalon, which forms the medulla. The two other flexures, the cephalic and the cervical, flex in a direction opposite that of the pontine

Question 63

Congenital absence of neural crest cells could result in: A. absence of sympathetic chain ganglia B. facial malformations C. absence of adrenal medulla D. absence of pigment cells E. all of the above are correct

Answer 63

E. is correct. ## Footnote Neural crest cells form all sensory and autonomic ganglia, Schwann cells, meninges of the brain and spinal cord, adrenal medulla, pigment cells of the skin and connective tissues of the head and neck, including odontoblasts for dentin of the teeth.

Question 64

With respect to the nervous system, which of the following is NOT correct: A. a muscle's nerve supply can be used as an indicator of its level of origin and path of migration B. Rathke's pouch is an outgrowth of oral ectoderm that becomes the anterior lobe of the hypophysis C. the sulcus limitans marks the boundary between motor and sensory areas D. sensory nuclei in the hindbrain lie ventral to motor nuclei

Answer 64

D. is correct. The nerve supply travels with the muscle, indicating its origin and migration path. Rathke's pouch, from which the anterior pituitary is formed, is from oral ectoderm. Sulcus limitans divides motor and sensory areas. Sensory nuclei in the hindbrain lie dorsal to the motor nuclei.

Question 65

In the development of the nervous system: A. the neural groove forms from the neural plate B. the neural folds are composed of neuroepithelial cells C. the neural tube maintains temporary contact with the amniotic cavity via neuropores D. neuroepithelial cells give rise to both neuroblasts and glia blasts E. all of the above are correct

Answer 65

**E. is correct**. The neural groove forms the neural plate when lateral parts of the plate elevate to form neural folds. Neural folds are composed of neuroepithelium which gives rise to neuroblasts, gliablasts and ependymal cells. After the neural tube forms, it maintains contact with the amniotic cavity via cranial and caudal neuropores.

Question 66

In the development of the nervous system: A. the sulcus limitans is found in the diencephalon B. the infundibulum is an outgrowth of the telencephalon that develops into the neurohypophysis C. sensory nuclei in the hindbrain lie ventral to the sulcus limitans D. the inner ear is derived from surface ectoderm

Answer 66

D. is correct. The sulcus limitans is a lateral, longitudinal groove dividing basal and alar plates. The infundibulum is an outpouching of the hypothalamic region that becomes neurohypophysis. Sensory nuclei lie dorsal to the sulcus limitans. Internal ear is from thickened surface ectoderm (otic placode) near rhombencephalon

Question 67

In the development of the nervous system: A. there are five primary brain vesicles B. during the 5th week, each brain vesicle subdivides into 2 parts C. the pontine flexure is in a direction opposite the mesencephalic and cervical flexure D. neural epithelial cells are found in the marginal layer

Answer 67

C. is correct. There are initially 3 brain vesicles: prosencephalon, mesencephalon and rhombencephalon. The pros- and rhombencephalon divide into 2 parts. The pontine flexure is opposite to the mesencephalic and cervical flexures. The marginal layer contains the nerve fibers arising from the neuroblasts.

Question 68

Cerebrospinal fluid: A. is produced in choroid plexuses B. circulates in the ventricular system of the brain and in the subarachnoid spaces C. re-enters the venous blood at the arachnoid D. granulations E. blockage of its circulation can lead to internal or external hydrocephalus F. all of the above are correct

Answer 68

E. is correct. Cerebrospinal fluid is produced by ependymal cells of the choroid plexus. It circulates within the ventricles of the brain, the central canal of the spinal cord and the subarachnoid space. It is resorbed into the venous system via arachnoid granulations. If flow is blocked, CSF accumulates and creates hydrocephalus.

Question 69

Of the following, the one most closely associated with the 3rd ventricle is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencephalon

Answer 69

B. is correct. The 3rd ventricle lies within the thalamic area in the diencephalon. The lateral ventricles are cavities of the forebrain cerebral vesicles, from telencephalon. The 4th ventricle lies within the metencephalon.

Question 70

Of the following, the one most closely associated with the cerebrum is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencephalon

Answer 70

A. is correct. The cerebrum arises from the telencephalon. Telencephalon, the most rostral part of the brain vesicles, develops from the prosencephalon as lateral outgrowths, the cerebral hemispheres and an intermediate area, the lamina terminalis. Lamina terminalis develops into the commissures connecting the hemispheres

Question 71

. Of the following, the item most closely associated with the pons is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencephalon

Answer 71

D. is correct. The metencephalon differentiates into the cerebellum, the coordination center for posture and movement and the pons, which serves as a neural relay center.

Question 72

Of the following, the one most closely associated with the efferent ducts of the testes is: A. mesonephric tubules B. mesonephric duct C. paramesonephric duct D. genital swellings E. urogenital sinus

Answer 72

A. is correct. The efferent ductules of the testes are the only functional derivatives of the mesonephric tubules.

Question 73

Of the following, the one most closely associated with the vestibule in the female is: A. mesonephric tubules B. mesonephric duct C. paramesonephric duct D. genital swellings E. urogenital sinus

Answer 73

E. is correct. In the male, the urogenital sinus gives rise to the urinary bladder, all but distal urethra, prostate and bulbourethral glands. In the female, it gives rise to the urinary bladder, urethra, lower part of vagina, vestibule, urethral and paraurethral glands and greater vestibular glands.

Question 74

Of the following, the one most closely associated with the urethra in the female is: A. mesonephric tubules B. mesonephric duct C. paramesonephric duct D. genital swellings E. urogenital sinus

Answer 74

E. is correct. In the male, the urogenital sinus gives rise to the urinary bladder, prostate, bulbourethral glands and all but distal urethral. In the female, it gives rise to the urinary bladder, urethra, lower part of vagina, vestibule, urethral and paraurethral glands and greater vestibular glands.

Question 75

Which of the following associations are correct? A. renal pelvis - ureteric bud B. ureter - ureteric bud C. urethra - urogenital sinus D. median umbilical ligament - urachus E. all of the above are correct

Answer 75

E. is correct. ## Footnote Ureteric bud gives rise to everything from collecting ducts through ureters. Derivatives of UG sinus include bladder and urethra of both sexes, prostate and bulbourethral glands, lower vagina and urethral, paraurethral and vestibular lands. Allantois becomes urachus, which then becomes median umbilical ligament.

Question 76

Embryologically, each uriniferous tubule consists of two parts which become confluent at the junction of the: A. ascending limb of Henle's loop and the distal convoluted tubule B. renal corpuscle and the proximal convoluted tubule C. descending and ascending limbs of the loop of Henle D. proximal convoluted tubule and the loop of Henle E. distal convoluted tubule and the collecting tubule

Answer 76

E. is correct. ## Footnote Everything from Bowman's capsule to the distal convoluted tubule develops from the metanephric cap. Everything from the collecting tubules through the ureter develops from the ureteric bud. Therefore the junction between the two occurs between the distal convoluted tubule and the collecting tubule.

Question 77

The ureteric bud appears as an outgrowth from the: A. metanephric mass B. lateral plate mesoderm C. urogenital sinus D. allantoic duct E. mesonephric duct

Answer 77

E. is correct. ## Footnote The ureteric bud is an outgrowth of the mesonephric duct. It forms the ureter, renal pelvis, calyces and collecting ducts

Question 78

The paramesonephric ducts in female embryos give rise to the: A. uterine tubes and uterus B. epoohoron C. inferior fifth of the vagina D. round ligament of the uterus E. ovarian ligament

Answer 78

A. is correct. ## Footnote The paramesonephric ducts in the female develop in the uterine tubes, the uterus and the upper 1/3 of the vagina. The epoophoron come fromthr mesonephric tubules. The lower portion of the vagina develops from the urogenital sinus. The round ligament and the ovarian ligament are from the gubernaculum.

Question 79

Which of the following gives rise to the labia majora? A. genital folds B. genital swellings C. genital tubercle D. urorectal gold E. inguinal fold

Answer 79

B. is correct. ## Footnote Labia majora arise from the genital swellings. Their counterpart in the male is the scrotum, which also arises from the genital swellings. The genital tubercle forms the distal end of penis and most of clitoris.

Question 80

The optic nerve is derived from what embryonic tissue? A. neural crest B. head mesenchyme C. endoderm D. mesoderm E. ectoderm

Answer 80

E. is correct. ## Footnote The optic nerve is derived from nervous tissue, therefore ectoderm, but not neural crest. Optic sulci of the neural folds forming the forebrain send out the optic vesicles, which then develop into the optic cups connected to forebrain by the optic stalk. The optic stalk becomes the optic nerve

Question 81

Neural crest cells differentiate into: A. postganglionic sympathetic cell bodies B. cells of the inferior mesenteric ganglion C. adrenal medullary cells D. cells of the enteric plexus E. all of the above are correct

Answer 81

E. is correct. ## Footnote Neural crest cells give rise to the peripheral parts of the autonomic nervous system, which includes all sympathetic and parasympathetic ganglia. Neural crest cells form all sensory ganglia of the peripheral nervous system. Neural crest cells also populate the adrenal medulla.

Question 82

the following, the item most closely associated with the regulation of visceral and endocrine functions is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencehalon

Answer 82

B. is correct. ## Footnote The hypothalamus of the diencephalon is the control center for visceral and endocrine functions.

Question 83

Of the following, the item most closely associated with the pons is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencephalon

Answer 83

D. is correct. The metencephalon differentiates into the cerebellum, the coordination center for posture and movement and the pons, which serves as a neural relay center.

Question 84

Of the following, the one most closely associated with the cerebrum is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencephalon

Answer 84

A. is correct. ## Footnote The cerebrum arises from the telencephalon. Telencephalon, the most rostral part of the brain vesicles, develops from the prosencephalon as lateral outgrowths, the cerebral hemispheres and an intermediate area, the lamina terminalis. Lamina terminalis develops into the commissures connecting the hemispheres.

Question 85

Of the following, the one most closely associated with the 3rd ventricle is: A. telencephalon B. diencephalon C. mesencephalon D. metencephalon E. myelencephalon

Answer 85

B. is correct. ## Footnote The 3rd ventricle lies within the thalamic area in the diencephalon. The lateral ventricles are cavities of the forebrain cerebral vesicles, from telencephalon. The 4th ventricle lies within the metencephalon.

Question 86

. Cerebrospinal fluid: A. is produced in choroid plexuses B. circulates in the ventricular system of the brain and in the subarachnoid spaces C. re-enters the venous blood at the arachnoid D. granulations E. blockage of its circulation can lead to internal or external hydrocephalus F. all of the above are correct

Answer 86

E. is correct. ## Footnote Cerebrospinal fluid is produced by ependymal cells of the choroid plexus. It circulates within the ventricles of the brain, the central canal of the spinal cord and the subarachnoid space. It is resorbed into the venous system via arachnoid granulations. If flow is blocked, CSF accumulates and creates hydrocephalus

Question 87

The fetal right atrium is mainly derived from: A. primitive pulmonary vein B. primitive atrium C. right pulmonary vein D. sinus venarum E. sinus venosus

Answer 87

E. is correct. ## Footnote The right sinus horn of the sinus venosus enlarges and forms the fetal right atrium. The left sinus horn regresses to form the main vein draining the heart muscle, the coronary sinus. The original right atrium becomes the right auricle and also part of right atrium anterior to the crista terminalis.

Question 88

. The sinus venosus: A. has a right horn which persists in the adult as the coronary sinus B. has a left venous valve which develops into the valve of the coronary sinus C. forms the smooth-walled portion of the adult right atrium D. receives blood directly from the portal vein

Answer 88

C. is correct. ## Footnote The left sinus horn regresses and persists as the main vein of the heart, the coronary sinus, whose valve arises from the inferior part of the right venous valve. The right sinus horn is incorporated into the right atrium, where it forms the smooth-walled part. The portal vein does not send blood to the sinus venosus.

Question 89

The following are true statements with regard to the fetal circulation EXCEPT: **A**. Since the fetal liver is a hemopoietic organ, it is large and well supplied with oxygenated blood. **B**. Fetal brain receives relatively pure arterial blood. **C**. Fetal and maternal blood vessels anastomose in the placenta **D.** In early developmental stages, one pulmonary vein buds from the left atrium of the heart. **E.** Foramen primum of the interatrial septum closes after the formation of the foramen secundum.

Answer 89

C. is correct. ## Footnote In the placenta, there is no anastomosis between the maternal and fetal vessels. Maternal blood from the spiral arteries enters the cotyledons, where it bathes the villi from the fetus. This all occurs without anastomosis.

Question 90

. The heart is derived from: A. splanchnic mesoderm B. somatic mesoderm C. septum transversum D. intermediate mesoderm E. paraxial mesoderm

Answer 90

A. is correct ## Footnote The heart tubes form within the cardiogenic region cranial to the oropharyngeal membrane and beneath the intraembryonic coelom. If it is beneath the intraembryonic coelom, then it lies toward the yolk sac and must be splanchnic mesoderm. Somatic mesoderm would be the other side, or roof, of the intraembryonic coelom.

Question 91

As a resident in pediatrics, you are called to see a newborn who has a unilateral cleft lip and a unilateral cleft of the primary palate. This condition is most likely the result of: A. failure of fusion of the mandibular prominences B. failure of fusion of the medial nasal processes C. failure of fusion of the maxillary prominence with the medial nasal prominence D. failure of fusion of the lateral palatine processes with the nasal septum E. failure of fusion of the paired lateral palatine processes.

Answer 91

C. is correct. ## Footnote This type of cleft is a failure of fusion, or secondary rupture of the union, of maxillary prominence with medial nasal prominence. If the palatine shelves or processes of maxillary prominences rupture or fail to fuse, a midline defect of the secondary palate will result.

Question 92

After folding of the head region, the structure lying just caudal to the pericardial cavity is the: A. developing heart B. connecting stalk C. primitive streak D. liver E. septum transversum

Answer 92

**E. is correct.** ## Footnote The septum transversum is the diaphragm's earliest progenitor. After folding of the head region brings the heart and its coleom region ventrally, the septum transversum is the structure that lies immediately caudal to it. Liver is not a bad guess, but remember that the diaphragm lies between it and the thorax in the adult.

Question 93

The following peritoneal ligaments are derived wholly or in part from the embryonic dorsal mesogastrium EXCEPT: A. hepatogastric ligament B. splenorenal or lienorenal ligament C. gastrosplenic or gastrolienal ligament D. gastrocolic ligament E. transverse mesocolon

Answer 93

A. is correct. ## Footnote Splenorenal, gastrosplenic and gastrocolic ligaments are derived from the dorsal mesogastrium, while transverse mesocolon fuses with dorsal mesogastrium. The nepatogastric ligament, on the other hand, is derived from the ventral mesentery.

Question 94

Failure of the brain to grow may result in: A. plagiocephaly B. craniostenosis C. acrocephaly D. scaphocephaly E. microcephaly

Answer 94

E. is correct. ## Footnote If the brain does not grow, neither will the skull. This results in microcephaly. Premature closure of cranial sutures is called craniostenosis. Early sagittal suture fusion causes scaphocephaly or a long skull. Early coronal fusion causes acrocephaly or tower skull. Asymmetric fusions produce plagiocephaly.

Question 95

Large (Giant) Oocyte has about ............of volume of normal size oocyte,

Answer 95

Large (Giant) Oocyte ( ≈200 µm) has about **twice** of volume of normal size oocyte,