Question 1

Incomplete fusion of two medial nasal swelling results in the production of?

Accepted Answer

Answer reason: The upper lip forms through fusion of the two medial nasal swellings with the maxillary prominences. Failure of the two medial nasal swellings to fuse results specifically in a median (medial) cleft lip, a rare midline facial defect. Lateral clefts involve maxillary–medial nasal fusion failure, not medial–medial fusion.

Question 2

Failure of the foramen ovale to close will lead to?

Accepted Answer

Answer reason: The foramen ovale is a fetal interatrial opening that normally closes after birth. Failure to close results in a patent foramen ovale, which is an atrial septal defect.

Question 3

What is the first organ to develop in the fetus?

Accepted Answer

Answer reason: The heart is the first functional organ to form in the embryo, beginning to beat and circulate blood by about week 3.

Question 4

What is the first organ that develops in the fetus?

Accepted Answer

Answer reason: The embryonic heart is the first functional organ to form and begins beating around week 3 of gestation, earlier than the brain, liver, kidneys, and lungs.

Question 5

Which organ develops first in the fetus?

Accepted Answer

Answer reason: The heart is the first functional organ to form; cardiogenesis begins in week 3, and it starts beating early in embryonic development.

Question 6

What is the most common type of twin pregnancy?

Accepted Answer

Answer reason: Dizygotic (fraternal) twins result from the fertilization of two separate ova and are far more common than monozygotic, conjoined, or monoamniotic twins.

Question 7

What is the most common type of tracheoesophageal fistula?

Accepted Answer

Answer reason: Type C (esophageal atresia with a distal tracheoesophageal fistula) accounts for the vast majority of TEF cases, approximately 85%.

Question 8

Incomplete fusion of the two medial nasal swellings results in the production of?

Accepted Answer

Answer reason: The two medial nasal prominences normally fuse to form the intermaxillary segment and the philtrum of the upper lip. Failure of their fusion results in a median (medial) cleft of the upper lip. A lateral cleft involves failure of fusion between the maxillary and medial nasal prominences; macro- and microstomia involve maxillary–mandibular fusion defects; an oblique facial cleft involves maxillary–lateral nasal failure.

Question 9

At what week do the fetal kidneys start secreting urine?

Accepted Answer

Answer reason: The metanephric kidneys begin producing urine around the 10th week of gestation; fetal urine subsequently contributes to amniotic fluid volume.

Question 10

How many arteries and veins does the umbilical cord consist of?

Accepted Answer

Answer reason: The typical umbilical cord contains two umbilical arteries carrying deoxygenated blood from the fetus and one umbilical vein carrying oxygenated blood to the fetus.

Question 11

Which of the following brainstem nuclei is not derived from the alar plate?

Accepted Answer

Answer reason: Alar plate derivatives are primarily sensory (e.g., the inferior olivary nuclei and cerebellar nuclei, like the dentate). The hypoglossal nucleus is a somatic motor cranial nerve nucleus derived from the basal plate, not the alar plate.

Question 12

The umbilical cord is also known as?

Accepted Answer

Answer reason: The umbilical cord has historically been referred to as the navel string, connecting the fetus at the umbilicus to the placenta.

Question 13

The first bone to begin ossification is?

Accepted Answer

Answer reason: The clavicle is the first bone to ossify in the embryo, beginning intramembranous ossification around the 5th–6th week of gestation. Others, like the scaphoid, ossify much later.

Question 14

Which organ develops first in the embryo?

Accepted Answer

Answer reason: The heart is the first functional organ to form in the embryo, beginning to beat and circulate blood by about the third or fourth week of gestation.

Question 15

From which structure is the fetus formed?

Accepted Answer

Answer reason: The embryo (and thus the fetus) develops from the embryoblast, also called the inner cell mass, of the blastocyst. The trophoblast forms placenta-related tissues; morula and blastocyst are earlier stages, not the specific cell population forming the fetus.

Question 16

Through what does the blood from the pregnant mother reach the fetus?

Accepted Answer

Answer reason: Oxygenated maternal blood reaches the fetus via the placenta and then is carried to the fetus through the umbilical vein (within the cord).

Question 17

Prenatal in ovum period, how many days?

Accepted Answer

Answer reason: Prenatal development is divided into the ovum (germinal) period lasting about the first 14 days after fertilization, followed by the embryonic and fetal periods.

Question 18

The blood from the pregnant mother reaches the fetus through what?

Accepted Answer

Answer reason: Oxygenated maternal blood from the placenta reaches the fetus through the umbilical vein in the umbilical cord; the other options are incorrect or nonspecific.

Question 19

After birth, in a normal neonate, the ductus arteriosus becomes?

Accepted Answer

Answer reason: After birth the fetal ductus arteriosus closes and fibroses to form the ligamentum arteriosum; ductus venosus becomes ligamentum venosum and the umbilical vein becomes ligamentum teres.

Question 20

The fetus connects to the placenta by the umbilical cord; a normal umbilical cord contains...?

Accepted Answer

Answer reason: A normal umbilical cord contains two umbilical arteries and one umbilical vein; thus, one vein and two arteries.

Question 21

After birth, the umbilical artery collapses and forms?

Accepted Answer

Answer reason: Postnatally, the distal portions of the umbilical arteries obliterate and form the paired medial umbilical ligaments; the proximal parts persist as superior vesical arteries. Ligamentum arteriosum derives from the ductus arteriosus, and ligamentum venosum from the ductus venosus; the lateral umbilical fold contains the inferior epigastric vessels.

Question 22

After the birth of the baby, the foramen ovale closes and it becomes...?

Accepted Answer

Answer reason: After birth, increased left atrial pressure functionally closes the foramen ovale, which becomes the fossa ovalis. Ductus arteriosus becomes ligamentum arteriosum and ductus venosus becomes ligamentum venosum.

Question 23

At which week are fetal circulation functions well developed?

Accepted Answer

Answer reason: Fetoplacental circulation becomes well established by the end of the first trimester, around the 12th week.

Question 24

After birth, the umbilical vein collapses and forms?

Accepted Answer

Answer reason: Postnatally, the umbilical vein becomes the ligamentum teres hepatis (round ligament of the liver). Ductus venosus becomes ligamentum venosum, and ductus arteriosus becomes ligamentum arteriosum.

Question 25

A fertilized ovum is implanted in the uterus after?

Accepted Answer

Answer reason: Implantation (nidation) of the blastocyst typically begins about 6–7 days after fertilization; thus 7 days is the best option.

Question 26

The umbilical vein, carrying blood from the placenta, enters the foetus with?

Accepted Answer

Answer reason: In fetal circulation, the umbilical vein carries the most oxygenated blood from the placenta to the fetus with about 80% oxygen saturation.

Question 27

Oxygenated blood enters the fetal circulation from the umbilical vein via?

Accepted Answer

Answer reason: Oxygenated blood from the placenta travels through the umbilical vein and bypasses the liver via the ductus venosus to the inferior vena cava. The ductus arteriosus connects pulmonary artery to aorta, the foramen ovale shunts RA to LA, and the umbilical arteries carry deoxygenated blood to the placenta.

Question 28

Esophageal atresia may occur as a part of VATER group of anomalies. What does 'TE' stand for?

Accepted Answer

Answer reason: In the VATER/VACTERL association, TE refers to tracheoesophageal fistula (often with esophageal atresia).

Question 29

Communication between aorta and pulmonary artery in fetal circulation is known as........?

Accepted Answer

Answer reason: In fetal circulation, the ductus arteriosus connects the pulmonary artery to the aorta, bypassing the nonfunctioning lungs. Foramen ovale is an atrial shunt; ductus venosus connects the umbilical vein to the IVC; fossa ovalis is the postnatal remnant of the foramen ovale.

Question 30

The earliest organ to form and began function within the developing human is the?

Accepted Answer

Answer reason: The heart is the first functional organ in the embryo, beginning to beat and circulate blood around week 3–4 of development.

Question 31

Which information about developmental stages and milestones in a normally developing fetus should a nurse include?

Accepted Answer

Answer reason: Division of the embryonic cloaca into the urogenital tract and anorectal canal occurs during the first trimester; many references place this separation by about 12 weeks. Testicular descent to the scrotum occurs much later (third trimester), and the kidneys reach their final position by around 9 weeks, not 16.

Question 32

Which of the following changes does NOT occur to the fetal circulation within minutes of birth?

Accepted Answer

Answer reason: Immediately after birth, umbilical vessels constrict, the ductus venosus and ductus arteriosus begin functional closure, and the foramen ovale closes due to pressure changes. There is no physiologic constriction of a 'hepatic portal sinus' as an immediate postnatal change.

Question 33

What is the function of the foramen ovale in fetal circulation?

Accepted Answer

Answer reason: The foramen ovale connects the right and left atria in the fetus, allowing oxygenated blood from the IVC to bypass the nonfunctional lungs by flowing directly from the right atrium to the left atrium.

Question 34

What is the correct definition of the term fetus?

Accepted Answer

Answer reason: The fetal period begins at the end of the 8th week after conception (9th gestational week) and lasts until birth; earlier is the embryonic stage.

Question 35

What is phocomelia?

Accepted Answer

Answer reason: Phocomelia is a congenital limb defect characterized by absence or severe hypoplasia of the long bones, producing flipper-like limbs. B describes anencephaly; C refers to duplication anomalies.

Question 36

At which age does the human fetus start to secrete the hormone thyroxin?

Accepted Answer

Answer reason: The fetal thyroid begins iodine trapping and hormone synthesis around 10–12 weeks of gestation, so thyroxine secretion starts near the 12th week.

Question 37

How many vessels are normally present in the umbilical cord after delivery?

Accepted Answer

Answer reason: A normal umbilical cord contains three vessels: two arteries and one vein.

Question 38

Failure of the foramen ovale to close causes what congenital heart disease?

Accepted Answer

Answer reason: Persistence of the foramen ovale results in a patent foramen ovale, a type of atrial septal defect. The other options involve different congenital cardiac abnormalities.

Question 39

Which of the following structures is NOT necessary for blastocyst implantation?

Accepted Answer

Answer reason: Successful implantation requires the blastocyst to hatch from and shed the zona pellucida so trophoblast (syncytiotrophoblast and cytotrophoblast) can invade the receptive, progesterone-primed functional endometrium. Therefore the zona pellucida is not necessary and must be absent.

Question 40

How many arteries and veins are present in the umbilical cord?

Accepted Answer

Answer reason: The normal umbilical cord contains two umbilical arteries and one umbilical vein.

Question 41

At what week can fetal gender be determined?

Accepted Answer

Answer reason: External genitalia are sufficiently differentiated to identify fetal sex by ultrasound around 12 weeks of gestation.

Question 42

At what time does ossification start in the fetus?

Accepted Answer

Answer reason: The first fetal bone to ossify (clavicle) begins intramembranous ossification around the 5th week of gestation.

Question 43

What is the first organ that develops in the fetus?

Accepted Answer

Answer reason: The heart is the first functional organ to form in the embryo, beginning to beat around week 3–4 of gestation.

Question 44

Incomplete fusion of two medial nasal swelling results in the production of?

Accepted Answer

Answer reason: The medial nasal swellings fuse to form the intermaxillary segment (philtrum). Failure of fusion between the two medial nasal swellings leads to a median cleft of the upper lip.

Question 45

Failure of foramen ovale to close causes which congenital heart disease?

Accepted Answer

Answer reason: The foramen ovale normally closes after birth as left atrial pressure rises. Failure of closure results in a patent foramen ovale, a form of atrial septal defect.

Question 46

During feto-placental circulation, the shunt between atria is called?

Accepted Answer

Answer reason: The foramen ovale is the fetal interatrial shunt allowing blood to flow from the right atrium to the left atrium. Ductus venosus bypasses the liver, ductus arteriosus connects pulmonary artery to aorta, and foramen magnum is a skull opening.

Question 47

What is the average length of the umbilical cord in centimeters?

Accepted Answer

Answer reason: The umbilical cord typically measures about 50–60 cm at term; 60 cm is the standard average among the choices.

Question 48

Which of the following drugs is a known fetal teratogen?

Accepted Answer

Answer reason: Alcohol is a well-established teratogen that causes fetal alcohol spectrum disorders with craniofacial, growth, and neurodevelopmental defects. The others are harmful but not classic teratogens.

Question 49

The cell from which the human body develops is known as?

Accepted Answer

Answer reason: A zygote is the fertilized egg cell formed by fusion of ovum and sperm and is the single cell from which the entire human body develops. Ovum and sperm are gametes, and 'overy' is an organ, not a cell.

Question 50

Which of the following medications is NOT associated with central nervous system abnormalities?

Accepted Answer

Answer reason: Valproic acid, methotrexate, and carbamazepine (Tegretol) are linked to neural tube/CNS defects; excess vitamin A derivatives (retinoids such as isotretinoin) causes CNS and craniofacial anomalies. Thalidomide classically causes limb reduction defects, not CNS abnormalities.

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Incomplete fusion of two medial nasal swelling results in the production of?

Failure of the foramen ovale to close will lead to?

What is the first organ to develop in the fetus?

What is the first organ that develops in the fetus?

Which organ develops first in the fetus?

What is the most common type of twin pregnancy?

What is the most common type of tracheoesophageal fistula?

Incomplete fusion of the two medial nasal swellings results in the production of?

At what week do the fetal kidneys start secreting urine?

How many arteries and veins does the umbilical cord consist of?

Which of the following brainstem nuclei is not derived from the alar plate?

The umbilical cord is also known as?

The first bone to begin ossification is?

Which organ develops first in the embryo?

From which structure is the fetus formed?

Through what does the blood from the pregnant mother reach the fetus?

Prenatal in ovum period, how many days?

The blood from the pregnant mother reaches the fetus through what?

After birth, in a normal neonate, the ductus arteriosus becomes?

The fetus connects to the placenta by the umbilical cord; a normal umbilical cord contains...?

After birth, the umbilical artery collapses and forms?

After the birth of the baby, the foramen ovale closes and it becomes...?

At which week are fetal circulation functions well developed?

After birth, the umbilical vein collapses and forms?

A fertilized ovum is implanted in the uterus after?

The umbilical vein, carrying blood from the placenta, enters the foetus with?

Oxygenated blood enters the fetal circulation from the umbilical vein via?

Esophageal atresia may occur as a part of VATER group of anomalies. What does 'TE' stand for?

Communication between aorta and pulmonary artery in fetal circulation is known as........?

The earliest organ to form and began function within the developing human is the?

Which information about developmental stages and milestones in a normally developing fetus should a nurse include?

Which of the following changes does NOT occur to the fetal circulation within minutes of birth?

What is the function of the foramen ovale in fetal circulation?

What is the correct definition of the term fetus?

What is phocomelia?

At which age does the human fetus start to secrete the hormone thyroxin?

How many vessels are normally present in the umbilical cord after delivery?

Failure of the foramen ovale to close causes what congenital heart disease?

Which of the following structures is NOT necessary for blastocyst implantation?

How many arteries and veins are present in the umbilical cord?

At what week can fetal gender be determined?

At what time does ossification start in the fetus?

What is the first organ that develops in the fetus?

Incomplete fusion of two medial nasal swelling results in the production of?

Failure of foramen ovale to close causes which congenital heart disease?

During feto-placental circulation, the shunt between atria is called?

What is the average length of the umbilical cord in centimeters?

Which of the following drugs is a known fetal teratogen?

The cell from which the human body develops is known as?

Which of the following medications is NOT associated with central nervous system abnormalities?

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