AN223

What would be the correct order of the following events during fertilization? 1 Digestion of zona pellucida by acrosomal enzymes 2 Sperm bypasses corona radiata 3 Cortical granules release enzymes 4 Sperm binding with vitelline membrane

2 1 3 4

The process of gastrulation occurs during which week of development? 1 2 3 4

3 (gastrulation creates '3' layers)

Journey of the morula through the Fallopian tupe takes usually: 1 to 2 days 3 to 4 days 5 to 7 days 8 to 10 days

3 to 4 days

When does differentiation of somites (somitogenesis) begin? In 3rd week In 4th week In 5th week In 6th week

3rd week

When does the implantation start? Immediately after fertilization 3rd day after fertilization 6th day after fertilization 9th day after fertilization

6th day

What is a serous membrane?

A thin, continuous membrane lining a closed cavity of the body and covering its organs - doesnt touch outside of body

A radioactive marker was applied to the mesoderm of a mammalian embryo. Which tissues or organs would have this marker in the adult? Spine and Brain Skin and Intestines Bones and Muscles Muscles and Skin

Bones and Muscles

What is a capacitation? Capacitation is a process in which the glycoprotein layer over the acrosome is dissolved Capacitation is a process in which sperm penetrates zona pellucida Capacitation is a process in which the tail of the sperm is inactivated Capacitation is a process in which the tail of the sperm is activated

Capacitation is a process in which the glycoprotein layer over the acrosome is dissolved

How to describe the origin of the intraembryonic mesoderm? Cells from the primitive node (node of Henlen) migrate between ectoderm and endoderm Cells from the wall of the amnionic sack migrate between ectoderm and endoderm Cells from the wall of the yolk sack migrate between ectoderm and endoderm Cells from primitive streak migrate between ectoderm and endoderm

Cells from primitive streak migrate between ectoderm and endoderm

All but one of following statements about the cleavage are true. Which of them is false? Cleavage occurs when the embryo travels through the Fallopian tube During cleavage, the amount of DNA inside the embryo increases Embryo is closed inside zona pellucida during cleavage Cleavage continues after implantation

Cleavage continues after implantation

what separates hind gut from proctodeum?

Cloacal Membrane

What is the function of sonic hedgehog siganlling pathway?

Control of radial patterning

What is recanalisation?

During the solid stage of development the endoderm of the gut tube proliferates until the gut is a solid tube. A process of recanalization restores the lumen.

The lungs, spine and muscles are derived from 3 different germ layers. What would be the correct order of formation of the embryological cells from which these tissues are derived from? Embryological cells that will form spine will form first, followed by the muscles and then lungs Embryological cells that will form muscles will form first, followed by the lungs and then spine Embryological cells that will form muscles will form first, followed by the spine and then lungs Embryological cells that will form spine will form first, followed by the lungs and then muscles

Embryological cells that will form spine will form first, followed by the lungs and then muscles

Which structures form the bilaminar germ disk? Mesoderm and mesenchyme Epiblast and hypoblast Endoderm and ektoderm

Epiblast and hypoblast

what are the structures derived from ectoderm?

Epidermis of skin Cornea and lens of eye Nervous system

what are the structures derived from endoderm?

Epithelial lining of digestive and respiratory tracts, Lining of urethra, bladder and reproductive System Liver and pancreas

Which statement about 'formation of somites is correct? Formation of somites is gradual: Cranial somites start, caudal somites continue later on Formation of somites is gradual: Caudal somites start, cranial somites continue later on Timing of formation of somites is less or more chaotic All somites are formed at the same time

Formation of somites is gradual: Cranial somites start, caudal somites continue later on

Which of the following structures is NOT present following gastrulation?

Hypoblast The hypoblast is displaced by the epiblast during gastrulation

Where the fertilization occurs usually? In the infundibular part of the Fallopian tube In the ampullary part of the Fallopian tube Horn of the uterus (cornua uteri) Cavity of the uterus

In the ampullary part of the Fallopian tube

What would be a direct consequence of a single point mutation that modifies the proteins inside the acrosome? Inability to dissolve zona pellucida's glycocalyx Failure to complete spermatogenesis Impairment of Sperms motility Increased polyspermy

Inability to dissolve zona pellucida's glycocalyx

All of the following are directly involved with the implantation process except: decidual reaction progesterone epiblast invasion none of the above

Invasion

Which statement is true about the trophoblast? It differentiates into outer cytotrophoblast and inner syncytiotrophoblast It differentiates into inner cytotrophoblast and outer syncytiotrophoblast Structure called "trophoblast" does not exist during the development of humanIt does not differentiate further

It differentiates into inner cytotrophoblast and outer syncytiotrophoblast

Which statement about the amniotic sac is true? ( It is lined up by cells of ectoderm from its beginning It is lined up by cells of endoderm from its beginning It is composed of cells derived from the epiblast It disappears completely during the second week

It is composed of cells derived from the epiblast

Which of the following arises from the mesoderm? The Nervous System Primitive Gut Tube Liver Musculoskeletal System

Musculoskeletal System The nervous system arises from ectoderm, and the liver and primitive gut tube originate from endoderm

Which statement about the neural plate is true? Neural plate forms itself between the primitive node and cloacal membrane Neural plate is the basic structure for neural tube and neural crests Neural plate originates at the ventral side of the germ disc Neural plate is of endodermal origi

Neural plate is the basic structure for neural tube and neural crests

Which embryological stage divides the embryo in two halves establishing bilateral symmetry in mammals? Neurulation Organogenesis Cleavage Blastulation

Neuralation

Does the morula change its volume in the Fallopian tube? Yes, the volume undergoes three to five cycles of changes Yes, the volume decreases Yes, the volume increases No, the volume does not change

No, the volume does not change

what are the structures derived from mesoderm?

Notochord Musculoskeletal system Muscular layer of stomach, intestine etc Circulatory system

All but one of the following statements are true. Which of them is false? Number of oogonia grows especially during puberty Common fate of oogonia is death by apoptosis Oogonia are able undergo mitotic division Oogonia are diploid cells

Number of oogonia grows especially during puberty

Oogenesis and spermatogenesis describe the process of meiosis in females and males respectively. What statement about the two processes is true? Oogenesis forms two polar bodies while spermatogenesis only forms one Oogenesis produces a larger gamete than spermatogenesis Both produce the same number of viable gametes Both are halted in an intermediate step until puberty

Oogenesis produces a larger gamete than spermatogenesis

septum transversum

Primordium of the central tendon of the diaphragm lies between the pericardial cavity and the yolk sac, ventral to foregut and pleuroperitoneal canals

The ductus arteriosus carries blood between which two structures? Aorta to subclavian artery Pulmonary trunk to the aorta Pulmonary veins to left atrium Umbilical veins to the IVC

Pulmonary trunk to the aorta

The foramen ovale is a structure which initially forms in which part of the heart? Ventricular septum Septum secundum Septum primum None of the above

Septum secundum

Paraxial mesoderm give rise: Both somatopleura and splanchnopleura Intermediate mesoderm Chordal plate Somites

Somites

omental bursa

Space between the superficial and deep leaves of the greater omentum

What is the function of HOX genes?

They determine body plan - giving rise to regional specification due to cranio caudal patterning (localised expression in the endoderm and mesoderm)

What is a prechordal plate? Ventral thickening of endoderm Ventral thickening of ectoderm Dorsal thickening of endoderm Dorsal thickening of ectoderm

Ventral thickening of endoderm

What temporally connects the mid gut to the yolk sac?

Vitelline duct (primitive umbilical cord)

Which structure does not take place in the late blastocyst? Zona pellucida Trophoblast Embryoblast Cavity

Zona Pellucida

Which statement about the zona pellucida is true? Zona pellucida is a membrane surrounding the oocyte, it is composed mainly of glycoproteins Zona pellucida is a membrane surrounding the oocyte, it is composed mainly of glycolipids Zona pellucida is on the border between theca folliculi interna and externa Zona pellucida is another name for Slavjanski's membrane

Zona pellucida is a membrane surrounding the oocyte, it is composed mainly of glycoproteins

All of the following differentiate from the diencephalon EXCEPT: a. Temporal lobe b. Pineal gland c. Mammillary bodies d. Thalamus

a

Before birth, blood is shunted: a) Away from pulmonary circulation b) Towards pulmonary circulation c) No shunts present d) Both a & b, according to respiration

a

The shaft of the penis develops from which primitive structure? a) Urethral Folds b) Labioscrotal Swellings c) Genital Tubercle d) Urogenital sinus

a

Which is responsible for the differentiation of the bipotential gonad into a testis? a) SRY b) Mullerian-inhibiting Factor c) Testosterone d) DHT

a

Which lateral branches that aorta develop to make connection with the matured kidney? a. Renal arteries b. Pelvic arteries c. Common iliac arteries d. Thoracic artery

a

Which structure that starts condensing in the pelvic region that gives ride to metanephric mesoderm? a. Intermediate mesoderm b. Paraxial mesoderm c. Lateral plate mesoderm d. Somatic layer of lateral plate mesoderm

a

What is the cloacal membrane?

a closure of gut tube distally, sandwiched by ectoderm and endoderm an area where the basal membrane between endodermal and ectodermal epithelium could not be distinguished.

what is the neural crest?

a collection of cells near the dorsal margins of the closing neural tube in an embryo Formed when the neural tube separates from the surface ectoderm

what is the stomoduem?

a depression between the brain and pericardium in an embryo

What is the proctodeum?

a depression in the ectoderm of the anal region of a embryo

does lateral folding occur before or after intermediate mesoderm formation?

after

Ductus arteriosus is sensitive to all EXCEPT: a) Prostaglandins b) Leukotrienes c) Oxygen d) Bradykinin

b

What is the remnant of umbilical arteries? a) Ligamentum arteriosum b) Superior vesical artery c) Ligamentum teres hepatis d) Ligamentum venosum

b

Where does the urine from mesonephric duct get drained into in the primitive urinary system? a. Urogenital ridge b. Cloaca c. Allantois d. Bowman's capsule

b

Which structure below that will digress during the development of nephron? a. Glomerulus b. Pronephros c. Mesonephros d. Metanephros

b

Which structure that cloaca's anterior portion will give rise to? a. Anal canal b. Bladder and urethra c. Urogenital sinus d. Umbilical ligament

b

The following are structures of the male reproductive tract, EXCEPT a) Seminiferous tubules b) Paraurethral glands c) Cowper's glands d) Sertoli cells

b (found in females)

what is the primitive oral opening?

buccopharyngeal membrane

The following statements are FALSE except: a. The mantle zone of the neural tube is the middle layer where neurons and axons start forming. b. The alar plate is the ventral and lateral extension of the neural tube. c. There are five secondary vesicles formed from the prosencephalon, mesencephalon and rhombencephalon. d. Two mg folic acid should be taken by pregnant women daily to prevent neural tube defects.

c

The genital tubercle becomes what structure/s in females? a) Clitoris b) Vestibular bulbs c) Both A and B d) Neither A nor B

c

The gubernaculum develops into which structure in the female reproductive tract? a) Labia minora b) Fallopian tube c) Round ligament of uterus d) Bartholin's glands

c

What is the concentration of oxygen in Umbilical Artery? a) 15% b) 28% c) 58% d) 85%

c

What is the remnant of urachus? a) Medial umbilical ligament b) Lateral umbilical ligament c) Median umbilical ligament d) Ligamentum teres

c

Where does Bowman's capsule come from when the metanephros growth is in the process? a. Collecting tubule b. Distal convoluted tubule c. Proximal convoluted tubule d. Glomerulus

c

Which is NOT essential for maintenance of fetal circulation? a) Foramen ovale b) Ductus arteriosus c) Renal veins d) Inferior Vena Cava

c

Which is responsible for the differentiation of the external female genitalia? a) SRY b) Progesterone c) Estrogen d) Luteinizing Hormone

c

Which of the following secretes the Mullerian-inhibiting factor? a) Prostate gland b) Cowper's gland c) Sertoli cells d) Leydig cells

c

Which of the following was NOT derived from the urogenital sinus? a) Bladder b) Membranous urethra c) Penile urethra d) Prostatic urethra

c

Which structure carries the most oxygenated blood in fetus? a) Umbilical vein b) Renal vein c) Inferior vena cava d) Umbilical artery

c

Which structure that is formed due to invasion of ureteric bud to the metanephric mesoderm? a. Allantois b. Cloaca c. Renal pelvis d. Ureter

c

Which structure that separates cloaca into two distinct parts? a. Urogenital sinus b. Septum primum c. Urorectal septum d. Ostium primum

c

Ductus arteriosus connects pulmonary artery to which of the following? a) Pulmonary vein b) Foramen ovale c) Subclavian artery d) Aorta

d

In the absence of the SRY gene, which of the following occurs? a. The Mullerian duct regresses b. The cloaca splits into the urogenital sinus and anal canal c. The gubernaculum guides the descent of the testes into the scrotum d. The gonads will differentiate into ovaries

d

The following statements are TRUE except: a. Ectodermal cells start to proliferate by day 17. b. The neural folds and neural groove form by day 18. c. The neural groove completely involutes to form the neural tube by day 21. d. The anterior neuropore closes after the posterior neuropore, which fuses by day 24.

d

What is the fate of ureteric stalk that is formed when the ureteric bud grows? a. It will digress b. It will become anal canal c. It will become collecting tubule d. It will become ureter

d

Where does metanephros develop? a. Umbilical region b. Epigastric region c. Acral region d. Pelvic region

d

The paramesonephric duct becomes what structure/s in males? a) Epididymis b) Vas deferens c) Both A and B d) Neither A nor B

d (it degenerates)

What is a mesentry?

double layer of peritoneum that enclose an organ and connect it to the body wall

Which layer of the trilaminar disc gives rise to the nervous system? Endoderm Mesoderm Ectoderm All of the above

ectoderm

peritoneal ligaments

folds of peritoneum that connects an organ with another or abdominal wall

what does the intraembryonic coelom give rise to?

future thoracic/abdominal cavities (closed cavities)

what is the only primary vesicle that does not form a secondary vesicle?

mesencephalon

What is the intraembryonic coelom lined with?

mesoderm

Which term describes the formation of the neural tube? Neurolisation Neurulation Neurology Neuroectodermisation

neurulation

What direction does neural tube close?

rostral (cranial) to caudal

where do epithelial liver cords and biliary system grow into?

septum transversum

What is the peritoneum?

serous membrane of the abdominal cavity, smooth tissue that lines your abdominal/ pelvic cavity and surrounds organ

What is the peritoneal cavity?

space between visceral and parietal peritoneum

What is the pericardial cavity?

surrounds the heart; the serous membrane of the pericardial cavity is the pericardium

What is the pleural cavity?

the potential space between the parietal pleura and visceral pleura (forms lungs)

when does oesophagus reach its final position?

week 7

When does recanalization occur?

week 8 -10 (depending on book)

Two haploid gametes form together one cell which is called: Diploid gamete Embryoblast Zygote This question is wrong, gametes are diploid

zygote